The Law of Conservation of Detail as applied to buying things in video games: no matter the shop, all that they sell is stuff the protagonist needs.
Say you're in a city of thousands. Its inhabitants obviously have all sorts of material needs. Scattered all over the place are vending machines, supermarkets, drugstores, street bazaars, Matter Replicators or what have you. You'd think that there'd be all sorts of goods available to purchase, from household tools to silverware, from groceries to clothing, from newspapers to flowers, et cetera.
Instead, all that's in stock are weapons, ammo, armor and medkits. In other words, all the stuff that a hard-fightin' RPG hero might want, but not what an ordinary person does. You might be able to grab a snack, but only if it cures your wounds or Wizard Needs Food Badly.
Alternatively, say you're in a teeny tiny town with a handful of people. There's half-a-dozen houses, and a couple of shops. But still, their entire commercial economy is based around stuff like swords, Healing Potions, and Poké Balls. You'd think that the whole town would starve to death.
No wonder there's so much strife around when all you can buy with your paycheque is a shotgun.
If the game bothers with a Hand Wave, it might be stated that there are lots of things in the shop, but that the game only bothers to show you what's relevant to your quest. An Acceptable Break from Reality, as few people would enjoy searching through a menu full of Shop Fodder just to find the few products they actually want.
- Many Castlevania games have a shop of some sort where the player can buy useful items, and while they're often inside or near Dracula's Castle where such an inventory would make sense, other times they're in random locales. Castlevania: Order of Ecclesia is probably the worst offender, with some random town store selling health potions and armor that only Shanoa would have a reason to buy. There's also a chef in town whose food is so bad that only Shanoa bothers with him, though since her primary means of refilling her health is eating she's probably the single best customer he could ask for.
- Seen in most The Legend of Zelda games. The trope is taken to the extreme when items that Link will only need to purchase once (eg. Deku shield at the start of Ocarina of Time) become 'sold out'. Not only is the stock limited to things that help Link, it seems that they will sell them to no-one but Link, and as such don't replenish their stock once he's bought them.
- In The Legend of Zelda merchants only sold three items each, and they were strictly limited to items Link might need.
- The Legend of Zelda: Ocarina of Time:
- How many of Hyrule's population need magic refilling potions or heat-resistant tunics? The guidebooks Hand Wave the Goron Tunic by stating that Hylians used to mine in the area.
- Played for Laughs with the Magic Bean salesman. At the start he tells you that the beans aren't very popular, so he'll sell them cheap. Every time you buy one, he increases the price by 10 rupees and raves about how popular they're getting, even though you're obviously the only one buying them.
- The Legend of Zelda: Twilight Princess:
- You can actually see items for sale in a market, and you can pick them up ... But Link always puts them right back, for various reasons.
- It's later lampshaded, in the Oocca shop in the City in the Sky. The text below each item boils down to "Why do we even have these?"
- Link is single-handedly responsible for financing the repairs to a Broken Bridge. The man standing on the street in Castle Town doesn't seem to be collecting money from anybody else.
- The Legend of Zelda: The Wind Waker's auction house. Everything that's up for auction is something Link can use. There are things up for sale that people besides Link might want or need, but Link is the only one who will need all of them. Everybody will bid on something, even if it's something they probably couldn't use (why did that gossipy older lady just buy a treasure map when she probably doesn't have a boat?). But where it really smashes headlong into this is the fact that if anybody besides you wins the auction, you can leave the room and come back to find that they returned it to the auction for literally no reason and more often than not the person who bought and returned it is at the auction bidding on it again. The item will always be returned to the auction house until you win it.
- In The Legend of Zelda: Skyward Sword, Beedle lampshades this when you look at one of his "Sold Out" signs, and Peatrice the Item Check girl develops a crush on Link as no one else in Skyloft is using her services and she initially thinks he's constantly visiting specifically to see her.
- The Legend of Zelda: Breath of the Wild averts this in large part due to the setting. Not only Link can buy, sell and use items such as food and household labor tools, the people traveling outside of the settlements have plenty of reason to be buying the things that only Link seemed to use in other games now that Hyrule is a ruined kingdom swarming with ruthless monsters (and some travelers do get attacked on the road and can sometimes be seen fighting back).
- Averted in River City Ransom: A wide range of completely normal items can be purchased, and they all give stat increases. Unfortunately, the only way to find out exactly what an item does is to buy it. The exception is the secret magic shop in the underpass. Everything in the store is explicitly designed for combat, so did they set up shop and wait for years until some student decided he needed to lay waste to a rival school with a sword?
- The Thorntail Hollow shop in Star Fox Adventures does sell things that the locals would consider food (Dumbledang Pods and Grubtub Fungus), though both are available for free from the trees and standing around on the ground. It's just as well, then, that the entrance seems designed to keep out Thorntails and Earthwalkers. No wonder he's considering moving...
- Steamworld Dig takes place in an old Western town and the vast underground mine network beneath it. The town is almost entirely unpopulated except for a scarce few NPC's whose only purpose is to service the player character. In fact, progressing through the game is done by selling the gems acquired from the mines to an NPC, and the money gained from doing so is used to purchase essential upgrades.
- Indiana Jones and His Desktop Adventures: The village of Lucasio consists of two people who give you healing items, one Marcus who briefs you as to the main quest, one guy who acts as a tutorial, and you. One's got to wonder why Gabriela even keeps so many seats at her cantina. There's a grand total of two buildings other than the ones inhabited by the game-relevant people (and they're not enterable).
- BioShock: Creator-Driven Successor to the System Shock series, shares this trope, minus the video game cartridges, though in this case there is a machine that is explicitly for selling ammo. You'd think that firearms wouldn't be allowed to begin with inside an underwater city with big glass windows all over the place . . . of course you can only break the windows you are supposed to, so people in Rapture probably don't have to worry too much about property damage.
- In Borderlands, there are ammo, weapon, and medical vending machines, and while it does make sense that living on a Death World like Pandora would require such a thing, outside of the DLC, there's never any sign of any place selling the other necessities of life, like food and water.
- System Shock 2: all replicators inside the Von Braun and Rickenbacker ships sell only tools of death, gameplay-related hardware, medical supplies, and (health-boosting) food—the only exceptions are video game cartridges. Justified because the replicators simply turn currency from Nanomachines into products according to the user's profile, and that the machines were already reprogrammed to dispense these unconventional items due to the tumultuous situation on-board the Von Braun and Rickenbacker. Also worth noting is that the player can also hack into the vending machines in order to force them to dispense a wider range of items for less, so it's possible that the Mega-Corp that sponsored the Von Braun may well be money-hungry enough to sell soldiers bullets from vending machines,
- Averted in the Avernum series. Some shops sell various things that are of no use to adventurers (you can, of course, buy them, but they generally won't do you any good unless they're used in a sidequest), while others mention that other things are in the store, but show you only the items you would be interested in.
- Played with in Baldur's Gate II in Waukeen's promenade: there are several doors where clicking on them informs you that these shops contain furniture, earthenware and other sundries useless to an adventurer; however, you can only enter the shops that sell useful stuff.
- In Chrono Trigger, you can buy exactly the same items in every era. There's a caveman stocking up on robotic attachments, just to cater to that niche time traveller market.
- Averted by A Dance with Rogues, a fan-made expansion for Neverwinter Nights. There are shops in Betancuria that buy or sell only clothing, and one merchant in the southern portion of the city sells only dyes. You even get to go into a tea shop, but that is because the proprietor is a weapons instructor in his spare time and will train you to fight in his basement, you don't actually get to buy anything.
- Nearly every town in any Dragon Quest game has an item shop, weapon shop, and armor shop, yet it seems the hero and/or his/her party are the only ones who would ever need such things. Although it's played with in Dragon Quest IV, where you get to play as Taloon, one of the guys who works in these stores, and you see a whole bunch of NPC adventurers come through to buy and sell.
- Averted throughout most of The Elder Scrolls series, where in addition to the normal adventuring fare (weapons, armor, potions, spells, etc.), you can find shops selling items that the average citizenry would want or need (food, drinks, books, Shop Fodder, useless decorative clutter, etc.) as well.
- Averted in Fallout: New Vegas for the main game and Honest Hearts DLC. Played straight and justified in the other DLC:
- In Dead Money, the vending machines that accept Sierra Madre casino chips and the hologram vendors running the normal shops and casino tables that accept pre-war currency are still running for you to use. The chips actually contain circuitry and raw materials to replicate items and the vending machines accept codes for non-standard items for emergencies, allowing them to operate as a supply source.
- In Old World Blues, the Sink commissary is specifically mentioned/lampshaded as being able to accept bottle caps because of Mobius making them admissible as a test mode on the Sink, along with possibly believing they would become valid currency in a post-apocalyptic future.
- In Lonesome Road, the automated commissary system in Hopeville is able to accept common bottle caps because of an oversight by the designer making the normal commissary chips such a similar size and shape that the machines can be easily scammed.
- Most Final Fantasy and similar games follow this trope to a T; however, in an interesting addition, Final Fantasy VII let you spend the insane amount of cash you get while grinding to beat the Weapon bonus bosses by buying a villa. It's totally useless except for Bragging Rights (and a place to store a particular useless item you can collect several times).
- The auction house in Final Fantasy VI has an aversion of sorts in that it sometimes sells items that, while interesting, are not anything useful to your quest. And you can't buy them; some kid always convinces his father to blow ridiculous amounts of cash on the non-useful items (even if you have more money, you're prevented from bidding after the father gives his bid.) Amusing the first time or two, but if you're trying to get something good from the auction house, be prepared for several rounds of the same guy buying the same talking chocobo over and over.
- In Final Fantasy IV: The After Years, some towns can be visited in several chapters, and in each one of them the shop's contents change to suit whoever you're controlling. For example in Porom's chapter Mysidia's shops sell mage gear, while in Edge's chapter, while you control one of Edge's students who's spying, it sells Ninja gear. When both chapters happen simultaneously in-story. And that same shop sold Paladin gear in the original game. Of course the likely explanation is that the shop actually carries everything and the interface is showing only the gear that interests you.
- Averted in Final Fantasy XV, where your characters patronize the same restaurants and convenience stores as everybody else. Given the game's rather grounded approach, even things like a Healing Potion don't come from any sort of specialty shops — they're mundane sodas and energy drinks given a boost by Noctis' Royalty Superpower.
- Lampshaded in Final Fantasy Crystal Chronicles: Ring of Fates: you are the only thing keeping the magic shop in business.
- Lampshaded by Jade Empire:
- When you ask one particular merchant if he has any weapons or magic items:
Merchant Chiu: "I have a cloak so warm it's like a weapon against the cold. I have a scrubber so good that it cleans like magic."Spirit Monk: "You don't actually have anything I'd want, do you?"
- By the Magic Abacus, a celestial bureaucrat with the job of making sure the items you need are conveniently available exactly when you need them. He cuts corners by selling them to you himself (and overcharging for them).
- When you ask one particular merchant if he has any weapons or magic items:
- In King's Field II, any and all items sold by the character can be bought back... from the gravedigger in the starting town.
- Lampshaded in Legend of Legaia: After you free Drake Castle from the Mist, the shops reopen, and one lady remarks that they are now selling exclusively weapons and armor instead of meat and fresh vegetables.
- A prime example is in Lufia II: Rise of the Sinistrals, where a certain town contains a shop that deals only in items the main character has sold previously in the game. This despite the fact the character in question has never visited the town or even that particular continent before. Even the other NPCs are a little confused by this one.
- In Mass Effect Noveria has only a weapons/armor shop. On the Citadel, the marketplace has multiple shopkeepers but you're only allowed to talk to the ones that sell weapons. In the sequel, you can actually buy all kinds of touristy things, including light reading, model ships, tropical fish for your aquarium and alien porn!
- Averted in Monster Girl Quest: Paradox, where towns contain at least one and often multiple food shops. Food is fairly important in the game, as you can give it to enemies or allies to raise Relationship Values or use it as ingredients in cooking-related skills. You can even eat it directly to restore some HP, though there are much better options for healing. Additionally, some of the equipment you can buy is tools or clothing that normal people might wear.
- In Moonlighter it's up to Will to get Rynoka's economy in motion by gauging his prices correctly and investing in the town to get other merchants to come.
- In the first chapter of Neverwinter Nights: Shadows of Undrentide, it is heavily implied that the village herbalist sells things ordinary people actually use in addition to adventuring gear, but he only sells you adventuring gear.
- Persona 4 features a modern day, rural Japanese village as the setting, yet the item shop sells things like Vanish Balls, which serve as a guaranteed escape from combat, and GoHoMs, which teleport you out of the dungeons nobody else in the world knows about. Who in the village would ever need these?
- Some optional NPC dialogues mention that some of the supernatural phenomena your party is investigating has happened before, and there are a few hints that at least one of the shopkeepers has at least some idea of what you're really up to.
- Justified in Persona 3, where some of the shopkeepers are actually involved in the incident that created the dungeon our heroes explore.
- Magical gear in both games are implied (and at one point in P3, stated outright) to be seemingly mundane trinkets, medicine, junk food, and weapons that become magical or unnaturally effective in the hands of persona-users or in alternate dimensions like the TV World. The TV World in particular runs on the kind of fictional logic that demands items from an item shop do amazing things for those playing hero.
- Shops at the beginning of both parts of Persona 2 sell food, clothing, and other mundane items, averting this trope, but you can spread rumors that make various shops carry weapons and armor, among other things. And you're probably not the only one buying this stuff, given the escalating chaos over the course of the games.
- Averted in Persona 5, sensibly enough, being set in Tokyo. Most of the shops are grocery stores, music shops, drugstores and general convenience stores, etc., including such things as a shoe repair station (not that you'll need it). Anything out of the ordinary is bought under-the-counter at an extremely shady medical clinic and Yakuza-affiliated "model weapons shop".
- Pokémon has tiny villages with just a couple of houses and shop that sells nothing but Pokemon catching and healing items. The only place you can buy anything not Pokemon-related is the massive department store in the big city (Celadon, Goldenrod, etc.), and that one shop that sells bicycles so expensive that they cost more than your body weight in gold - in fact, they cost more than the maximum capacity of your wallet (yet will eventually give one away for free under various circumstances).
- Platinum features two bars and a restaurant. All of which are filled with people that want to fight you, and only one of the bars will sell you liquid refreshment: Moo-Moo Milk, which is used to heal Pokemon...
- Pokémon X and Y feature clothing and accessory stores, which let the player (and presumably other residents of the town) buy new outfits, hats, and bags.
- Rakenzarn Tales plays it straight in that the only shops you ever really visit are the ones for equipment and items. There's also the odd restaurant you can visit to buy food for stat boosts or get some to go.
- Rakenzarn Frontier Story justifies its use of this trope. Your only currency is Medals that you keep inexplicably finding on enemies and chests that are only valuable to inter-dimensional travelers, so you can't use them in any of the stores of the other worlds you visit. The Chamber of Rakenzarn, your home base, only sells stuff that Realmwalkers would use on the job, with the implication that anyone who does end up having to bunk there has to bring their own stuff from their home world.
- Played with by Recettear. The town involved is actually a haven for adventurers, so you have to sell them the stuff they need. However, Recettear clearly isn't the Only Shop in Town. Recette can visit the market to buy miscellaneous items to sell at a profit (Capitalism, ho!) and if you drive too hard a bargain, a customer will walk out.
- Shining Wisdom has one shop for the whole kingdom (okay there is one more hidden in the middle of nowhere, behind a rock, past a lake, which only the player can reach, and whose prices are insanely high) and he sells only three items. Only one of those could be of any possible use to anybody other than our hero.
- Justified in Shin Megami Tensei: Strange Journey: You literally are the economy... well, you and the other soldiers on the Schwartzwald mission. The items you "buy" are being supplied to you via a replicator powered by Macca (the Energy Economy of the game), using Forma (items retrieved from defeated demons) as the base matter. Likewise, items you "sell" are broken down into their base materials. As such, the reason you only find items relevant to gameplay in the "shop" is because that's what they're equipped to supply you with, and as you acquire new materials, the selection expands to accommodate this.
- Tales Series: While shops in this series inexplicably stock weapons for Improbable Weapon Users, Tales of Zestiria takes this trope further. It has a mechanic where shops can sell non-unique equipment they don't already have if the player sells it to them first, meaning the player can influence every shop's potential stock. However, the shops' random pool will eventually reset and stop stocking the new equipment until the player sells them another one.
- Generally averted in the Trails Series, where every establishment you visit, from stores to street vendors, is a legitimate business that deals with customers besides you on a regular basis. There are many Bracers besides you who need to make use of the weapon shops, after all. Some sidequests have you testing new products before they go on the mass-market. Lampshaded when a shopkeeper in Trails from Zero explains that after he got a shipment of orbal staves from Tio's boss, he's stuck with them, and figures she'd better buy his stock.
Gironde: Don't worry, though. I don't intend to sell these orbal staves to anyone but you, miss. Y'know, isn't selling them to me, only to sell to you sort of strange? I mean, I feel like there're better ways to go about that.
- Wasteland 2 is a world where everybody needs weapons but food is usually classified as junk. On the other hand, there are still traders for alcoholic drinks and drugs, so no wonder the world is a mess.
- Averted in World of Warcraft, there's plenty of random houses you can't go in and and people sell things like beer, toys, et cetra.
- A justified game mechanic in Xenoblade Chronicles 2. At the start of the game, the global economy is in steep recession due to habitable land quickly disappearing, leading to high prices and limited availability. As you complete sidequests, spend and make money, or even just chat to locals, an area's "Development Level" rises, lowering prices and allowing your mercenary force to help secure new contracts and trade route, leading to further development, new sidequests, and commentary from NPCs on how the improving economy leads to better quality of life. Eventually, you can start buying the deeds to various shops, giving you certain buffs and a cheery welcome from the shopkeeper.
- You can also buy a lot of mundane items from shops most games would leave out, everything from snacks to board games to cloth. Giving these "lifestyle items" to characters boosts their morale, which translates into stat bonuses for a duration.
- A first for video games, when you leave the dungeon in the 1974 dnd, you can buy items in Aumakua's Alchemy and Korona's Armory. Of course, each item is tailored to your adventuring experience and includes magical potions and weapons that no one but you has any use for.
- Dead Space:
- In Dead Space, it's implied that the automated stores were hacked by the crew of the Ishimura to provide equipment to fight the necromorphs, though it didn't work out too well for them.
- In Dead Space 2, all the stores aboard Titan Station, even those in the civilian sectors, only provide guns, ammo, health packs, stasis charges, etc. Justified, as the store welcomes the protagonist, Isaac Clark, by name, implying that the store is only displaying items he told it to display.
- Parodied in the Disgaea series, where the general store does sell things other than weapon or armor, but they're all either usable items or accessories you can equip.
- In Nobunaga's Ambition 2: Lord of Darkness for the SNES, the only things you can buy ACROSS THE WHOLE OF JAPAN are guns, rice, teacups and (in battle situations) horses. Sure, the platform has its programming limitations, but what about sushi? Fish? Bows? Arrows? Sake? Do they all walk around naked? All that gold and huge castles, with no place for the average Japanese to live.
- Played with across the Grand Theft Auto series:
- The only shops open for business in Grand Theft Auto III were gun shops.
- Averted in Grand Theft Auto: Vice City, where more types of shops were open for robbery, in Grand Theft Auto: Vice City Stories, where some shops were open for protection racket.
- Grand Theft Auto IV averted this. Just about everything that one would expect to be open for business, actually is. Bars, bowling alleys, fast food places, clothing stores, strip clubs, etc (although only two or three of each in the whole of
New YorkLiberty City...) No grocery stores though.
- Averted in Dwarf Fortress Adventure Mode — pretty much any human city will have multiple stores dedicated to things you have absolutely no need of — leather, furniture, basic clothing, bolts of cloth, jewelry and other assorted trinkets. It will also most likely have a market, which tend to be much more useful — there are usually loads of farmers there, who all sell edible plants.
- Played with in the first two installments of the Pokémon Mystery Dungeon series. On one hand, each has a town that seems oddly specific to rescue teams. Some could serve multiple functions, like the bank or Kecleon Shop, but what's an ordinary Pokemon going to do with a Link Shop or a Treasure-Box opening stall? On the other hand, virtually every Pokemon you meet in the towns are members of various teams, and the main items you use tend to be food items. Averted in the Gates to Infinity series, where you'll have to build most of the rescue team shops yourself.
- Exaggerated in Harvest Moon: A New Beginning, when you first arrive the place is a Ghost Town with only two inhabitants. Once the stores open up, they mostly sell farming seeds, recipes and blueprints, Most of which is useless to the villagers that later arrive.
- Averted in Story of Seasons (2014), where some other villagers are farmers, too, so they likely need the same stuff.
- Yes, Your Grace swings back and forth between justified cases and aversions.
- The justified aspect is that the merchants approach the Player Character rather than the other way around, so those who don't think their wares will interest a King don't bother visiting in the first place.
- On the aversion side, some of the merchants who have things to sell the Player Character have inventories consisting of what he actually needs to buy from them and various items that can technically be purchased, but are useless in terms of gameplay. There are even a couple merchants who only sell items that are a complete waste of gold.
- If a tabletop RPG features explicit price lists for items and services, expect a heavy (quite possibly total) focus on things the average player character adventurer is expected to need as par for the course. Other things and businesses handling them will obviously presumably exist in the game world, but if the details ever become important it'll be up to the game master to make something up on their own.
- Surprisingly averted in the tabletop RPG version of BattleTech, Mechwarrior. Books contain both availability and price stats for mundane items like food, lodging, transport, and personal items like tablet computers and Bluetooth headsets. It also included a surprisingly exhaustive list of clothing with no military application whatsoever, including differentiating between simple underwear and lingerie!
- d20 Modern is even worse than D&D about it. Aside from a small section on lifestyle needs — for if you want to buy a house or a car — almost everything in the various books' equipment chapters are geared toward satisfying the needs of action movie heroes. However, the game also runs on an abstract Wealth score instead of hard numbers, representing a character's overall financial situation. The abstraction makes it easy for the GM to estimate a rough Purchase DC for anything not on the equipment tables, allowing players to quickly buy what they want while reducing table bloat.
- Dungeons & Dragons has a reputation for being very guilty of this in its core rulebooks and many supplements, but has tried to avert it to varying degrees over the different editions. Core books will sometimes discuss the daily wages of common laborers which hang roughly together with the costs of food and lodging, as well as market prices for trade goods so the GM can reward player characters in kind instead of coin and leave it up to them to figure out how to turn bolts of cloth into cash. Some sourcebooks also discuss city life and its costs, building and maintaining a stronghold, or other features designed to expand the world beyond adventuring and explore what characters can do during their downtime other than buy new gear.