Alice and Bob are at a party and Bob starts to get a little hungry. So when he sees some food on a tray he helps himself to it. Cue Alice coming over and telling Bob he just ate the pet's food. Bob, being informed that unbeknownst to him that he was eating pet food, is either disgusted and spits the stuff out or shrugs and keeps eating the food.
Character in settings on the Wrong Side of the Tracks, or post-apocalyptic settings intentionally eating cans of pet food do not count as this trope, as the people know they are eating pet food.
In Real Life, pet food can be made with a lower grade of meat than is permitted for human consumption, which means that a wider range of meat and meat byproducts can be added. However, the most luxurious brands boast that they are made with human-grade products, so a mixup in the fridge could occur.
Similar to You're Drinking Breast Milk and sub-trope to I Ate WHAT?!. This is the unintentional version of Dog Food Diet. It might be caused because of the fancy-looking pet food packages, as Gourmet Pet Food is customary.
May be related to Feed by Example.
- A Butterfinger commercial featuring The Simpsons has Homer trying to steal Bart's Butterfinger bar during a power outage. Bart offers to give him a bite of it, but it isn't until the lights come back on that Homer realizes that he's been fed a dog biscuit.
- Implied in Dragon Ball Super in Trunks' Bad Future, when his friend Mai finds a can of food and excitedly points out "It's not even cat food, either!"
- Ishigami takes to eating fish food as a snack in Kaguya-sama: Love Is War after he starts exercising (as it's high in protein, low in fat, and fairly cheep). Fujiwara asks to have some and doesn't find out what it is until after she's already eaten one.
- In an early episode of Pokémon: The Original Series, Brock shows the gang the food he developed for Pokémon. The Cloudcuckoolander scientist who's joined them for the episode tries it (not accidentally, this is after Brock's shown it to the group) and says he likes it, but every other non-Pokémon character finds it disgusting.
- An earlier example has Ash deciding to sample the food Brock has made for Pikachu, which he immediately regrets. Brock mentions that while Pokémon can and do enjoy food made for humans, the reverse is rarely true.
- In "Sonic X" Chris feeds Sonic cat food because he read that hedgehogs love them.
- In Big Top Scooby-Doo!, animal trainer Doubleday absent-mindedly shoves a dog biscuit into Shaggy's mouth. Shaggy doesn't mind and eats it anyway. (Then again, this is Shaggy, who's canonically eaten Scooby Snacks of his own free will since the original series.)
- Fiona's dad King Harold in Shrek 2 absentmindedly starts eating the dog's breakfast. He actually thinks it tastes really good before finding out what it is.
- Bachelor Party: Debbie's friend Phoebe digs into a bowl of cat food at Debbie's shower thinking it's pate. She keeps chowing down after Debbie's mom tells her it's cat food.
- In the beginning of A Far Off Place Harry mistakes the cat food for pate. When he finds out what he ate, he is so embarrassed he takes another bite.
- In Gooby, during the store scene, Gooby starts eating random chips in the store rapidly and accidentally eats cat food. Justified, as the cat food was in what looked like a chips bag, next to the chips.
- In Lethal Weapon 3, Murtaugh gives Riggs a box of dog biscuits after getting frustrated with Riggs' failed attempts to quit smoking. Riggs takes a bit of one and finds that he likes it. As a Running Gag through the rest of the film, he occasionally chows on more dog biscuits.
- In Mrs. Brown, You've Got a Lovely Daughter, Herman invites the tramp Percy over for dinner. At the table, Percy has a bite of a dog biscuit and complains, "I say, these croutons are a bit hard."
- In The Prince of Tides, Lila is insulted that her boorish husband Henry ridicules her cooking for being too fancy, so, with her children's help, she fixes a hash that has dog food as the main ingredient. She sets this "dish" before Henry, who pronounces it quite tasty.
- In UHF, Weird Al accidentally feeds his co-host dog treats while filming a promo for butter cookies. His friend gags at the taste, but continues eating them until Al notices his error and transitions smoothly into a promo for the dog treats. His friend then runs off screen to vomit.
- In Superman III, Clark Kent enjoys eating what he thinks is pâté at a picnic with Lana Lang. She informs him that it's dog food, but he's not particularly fazed by the information.
- In Diary of a Wimpy Kid: The Long Haul, Rodrick eats gerbil pellets while he's in the waiting room after Greg gets bit by Manny's new baby pig. He doesn't seem to mind the taste.
- In the final chapter of Henry and Beezus, from the Henry Huggins series by Beverly Cleary, Henry is being teased relentlessly by friend and stranger alike after winning $50 in beauty treatment coupons for a local beauty salon in a raffle at the grand opening of the new hypermarket in town. To divert attention from this fact, he accepts a vendor's offer (earlier in the chapter) to taste dog food.
- In Henry Reed's Baby-Sitting Service, the eponymous main character winds up cooking hamburgers for his client's boss when his client can't make it home in time for the dinner, and he's complimented on the unique taste. After the event, his client asks him where he got the hamburger meat and it turns out that he used the horse meat meant for the dog.
- Played with in The Truth, where William revives his vampire friend Otto with a piece of blood. Otto is enthused that he received blood from high-quality steak, until William comments that it's pet food; Lord Vetinari doesn't go in for fancy eating, but he loves his dog.
- In 3rd Rock from the Sun, when Dick quits his job at the University, the aliens are reduced to eating cat food. Sally tries to convince them that they are actually eating cat, but Mary makes Tommy gag by pointing out to Dick that "Your son is eating cat food!"
- It's Always Sunny in Philadelphia: Charlie's bedtime routine involves eating cat food, drinking beer and huffing glue to help him sleep through the incessant yowling of the cats outside his apartment at night.
- Benson: Big Eater Pete sees a bowl of food on the kitchen table and eats it, not knowing that it is cat food for Katie's new kitten.
- In an episode of The Crazy Ones, the agency is loaned a cat food company's mascot for a few days so they can be "inspired" for their pitch. Simon sets out bowls of cat treats all over the office, and Andrew mistakes them for free snacks. He spits out the first handful, but later develops a taste for them, to the mockery of the others.
Andrew: It says human-grade, you elitist!
- Divorce Court: In the mid-1980s dramatized version, a woman fed up with her husband and boorish beer-drinking friends fixes chili con carne, not telling them until afterward that she had substituted dog food for the hamburger. (Fortunately, nobody got sick.)
- On Dual Survival, Cody and Dave once had nothing but a can of dog food to eat. As they're digging in, Cody mentions that American food regulations require pet food to be made suitable for human consumption because pet food sales spike during times of economic crisis.
- Frasier has Daphne feed Bebe Eddie's dog biscuits to get back at her for treating her like a servant.
- A much later episode has Frasier and his KACL coworkers participating in a weight loss contest. They become so hysterical for food, they fight each other over a bowl of bird seed. They don't know what it is, but by that point, they don't even care.
- The Golden Girls has Dorothy eating some Chicken food that Rose had left behind.
- Good Times: A 1975 episode, the Evanses' neighbor resorts to buying cheap dog food to eat when she can't afford regular food at the store. This causes some unintended unease with Florida when she invites her over for dinner and the neighbor offers to bring meatloaf. (Of course, in the end, the neighbor reveals she made the meatloaf ... from ground beef, but not until after dinner, when everyone is sure they've eaten Alpo.)
- Grange Hill: Trisha Yates asks Simon Shaw how he buys sweets if he can't read the names. Simon says he remembers the colours, but adds that he once went to the wrong counter, and ended up eating a packet of birdseed, which didn't taste too bad.
- On The Honeymooners, Alice takes care of a dog, and heats up some dog food on the stove. Ralph and Ed find it, unknowingly taste it and like it, which leads to Ralph taking a sample in for his boss to try in the hopes of making it into a commercial product. Unfortunately, one of his coworkers recognizes what it is.
- In an episode of Kenan & Kel, the duo decide to make a list of life goals to complete, and one of Kel's goals is to eat dog biscuits, which he does. He later carries the box around to snack on.
- One episode of Kitchen Nightmares has Gordon Ramsey ask a diner about the food. Said diner says it tastes like cat food. Gordon asks how he knows what cat food tastes like and the diner replies "Long story."
- In the Odd Squad episode "Can You Wrangle It?", Osemite wears two pouches, one filled with food for humans and the other filled with creature food. He accidentally eats from the latter pouch, but he ends up liking it and continues to eat it.
- Operation Ouch!: While doing a story about a medical detection dog named Daisy, Dr. Chris comments that Dr. Xand's breath smells like doggy snacks. Xand comments that he hasn't had any doggy snacks, but he did have some delicious biscuits he found on the floor on the way in. In a bowl. Marked 'Daisy'.
- Red Dwarf:
'Lister: (Looking at his mug in disgust) "Why didn't you tell me?"Holly: "What, and spoil your tea?"
- In one episode Lister discovers that the Dwarf ran out of their primary milk supply a long time ago and switched to the emergency backup supply, dog's milk. Apparently it tastes the same spoiled as it does fresh.
- "Marooned" features Lister and Rimmer stranded on a planet where their limited emergency supplies include tins of dog food. Lister would still rather eat that than a Pot Noodle, though.
- Season 1, Episode 3 of Saturday Night Live had an early "fake commercial" for "Felina Cat Food", where a woman was asked to sample tuna noodle casserole, one made with regular canned tuna, and one made with cat food. She found the cat food version "CHUNKIER! And, uh.. CREAMIER!" ... until it was revealed what she ate.
- On Schitt's Creek David Rose takes what he thinks is a cookie from a table at Ted's office, and Ted informs him it is a doggie treat.
- Season 7 of Shameless (US) introduces Etta, the elderly owner of Fiona's laundromat who, due to dementia, is prone to eating cat food.
- Three's Company had Mr. Roper eat some dog food he mistook for a stew Jack had whipped up.
- To Tell the Truth had one of these in a 1973 episode. Several sample dishes were set before the panel, and the dog food part was only revealed as host Garry Moore read from the affidavit, and announced their job was to identify who was promoting dog food as a cheaper alternative to the high meat prices of the early 1970s.
- The episode of The Worst Witch where the girls receive their cats features Miss Bat eating from a tin of cat food.
- Done on Will & Grace. Justified in that Will was so obsessed with his new dog that he was actually cooking food for it on the stovetop, when Grace came by and tasted it. Her response upon being told was a croaked-out "Needs salt".
- Would I Lie to You?: During a round of "This Is My...", Jason Manford claimed that the woman in question was the owner of his local cafe who had told him off for eating the treats she left out for customers' dogs. It was true.
- The last verse of Run–D.M.C.'s You Be Illin'
For dinner, you ate it, there is none leftIt was salty, with butter, and it was defYou proceeded to eat it 'cause you was in the moodBut Holmes, you did not read, it was a can of DOG FOOD!
Jon: (eating cat food) This tastes funny.Garfield: If you add water, it makes its own gravy.
- In this strip from 1951, Schroeder (then still a baby) eats out of Snoopy's food bowl. He enjoys the dog food so much, that he pushes Snoopy aside. In retaliation, Snoopy jumps into Schroeder's high chair to eat his baby food.
- In this strip from 1953, Linus (then still a baby) eats out of Snoopy's food bowl. Unlike Schroeder, however, Linus finds Snoopy's dog food tastes terrible.
- In The Men from the Ministry whenever One and Two are hiding an animal in the office Two is sometimes forced to eat the animal's food to fool Sir Gregory into thinking it's just his breakfast or medicine.
- Our Miss Brooks: In Poison Ivy, Mrs. Davis sets out dog biscuits in place of cereal for breakfast. Miss Brooks and Walter Denton both fall victim.
- Baten Kaitos has dog food as an item/weapon. Using it poisons the target and inflicts damage, so you can fight enemies by force-feeding them dog food until they die.
- The Long Dark also has canned dog food as one of the food items that can be scavenged. Again, the player can't really afford to be picky, considering the game's setting.
- 7 Days to Die has canned dog and cat food among the food items that can be scavenged. The player can't really afford to be picky, considering the game is set in a Zombie Apocalypse.
- Wolfenstein 3-D includes dog food on the list of health power-ups: it provides a 4% health boost when picked up. Of course, you won’t find any on levels without guard dogs.
- The Mystic Messenger April Fools Episode has Zen be given a strange “cereal” by Jumin as a birthday gift. Only when he has eaten some does Jumin inform him it's cat food. Turns out he somehow got sucked into another universe where Jumin is a talking cat (and the others are some form of Animate Inanimate Object), so he legitimately thought Zen would enjoy the gift.
- In Freefall, Florence the gengineered wolf has a fondness for ramen with kibble, claiming that the flavours work well together. When her roommates back in college found out... they agreed, and ended up stealing her kibble all the time.
- Subverted in League of Super Redundant Heroes: Keith tells Laser Pony (who's blind) that he's eating cat food instead of cereal. Laser Pony expresses disgust and dismay that he always mixes the boxes up. Then he digs back in when he's sure Keith is out of sight.
- In Aqua Teen Hunger Force episode "Working Stiffs", when the trio runs low on money, Frylock orders Shake and Meatwad to get into suitable work so they won't have to continue eating fish n' cheddar cat food.
- In the Bob's Burgers episode "There's No Business Like Mr. Business", Tina finds a box of Aunt Gayle's cat food, has a taste, and becomes utterly hooked on it. She then gives some to Gene, who likes it as well and soon both of them are scarfing it down. Then they discover that the box was Linda's, who had also developed a taste for it.
- In the Braceface episode "A Dog's Life" Adam eats some dog treats that were free samples at the pet store. He gags when he realizes what he's been eating...then immediately goes back to eating them.
- In the Courage the Cowardly Dog episode "Invisible Muriel", Eustace sneaks some bites of Muriel's latest cooking, thinking it was dinner. But when he found out moments later that what he ate was Muriel's batch of her "Secret Recipe Blue Ribbon Dog Food", he spits some of it out and tries scrubbing the taste off his tongue.
- Helen accidentally eats dog food in the first episode of Martha Speaks.
- Ready Jet Go!:
- In "Sunspot's Night Out", Cody goes missing and Mitchell leaves a trail of dog treats for him to find. Jet and the gang stumble upon the trail while trying to find Sunspot, who's also missing. Jet almost eats a dog treat, but his friends warn him not to.
- In "Pet Sounds", the gang is petsitting Cody and realize that he can do tricks if he gets treats as a reward. Jet ends up eating a dog treat, and remarks that it's better than the school cafeteria food on Bortron 7.
- The first episode, "Tommy's First Birthday", had Tommy convince the other babies to hunt down some dog food, thinking that it would make them into dogs. When they finally get to it and eat some, they immediately spit it out in disgust (except for Lil, who says that she likes it).
- "Runaway Angelica" has Angelica running away from home and hiding at Tommy's house. She orders the babies to get her some cookies, but when they can't reach the cookies on a high shelf, they opt to give her dog biscuits instead. Angelica eats them with enjoyment until the babies tell her what she's eating, she reacts with disgust and anger. The babies themselves don't understand and remark that they eat them all the time.
- Sponge Bob Square Pants:
- In "Missing Identity", SpongeBob comments that he has been feeding his pet snail Gary for years and doesn't even know what it tastes like. He doesn't like it, but later has to keep on eating it when he retraces his steps to find his eponymous identity.
- In the episodes Have You Seen This Snail and Gary's New Toy, Patrick is known to often eat pet food.
- In "Pineapple Fever", when Squidward locks himself in SpongeBob's room, he gets hungry and finds a bag of food to eat. When Gary wants to eat some, Squidward refuses to share until realizing that he's eating snail food and spits it out in disgust.
- One of the first side effects of SpongeBob's snail plasma injection is this in "I Was A Teenage Gary".
- Strawberry Shortcake Berry Bitty Adventures: Apple Dumplin' samples some of Strawberry's new biscuits, only to learn they're intended for dogs. Strawberry assures her that they're human-quality and that Strawberry herself ate several during the prep to make sure they were good, so there's nothing wrong about eating or even enjoying them, but Sour Grapes sees and starts bullying Apple about being a dog.