Adding to the first possible explanation, some people have theorized the player character might be disabled, since he is unable to move from his seat, and is paid less than minimum wage (even for his day). Since people with disabilities often have a harder time finding work and additionally tend to have higher medical expenses, if he is disabled that might explain why he's willing to stay.
The animatronics themselves. Are they simply machines with malfunctioning programming, or are they corrupted by being haunted? Likewise, there is debate over whether or not they're truly malevolent or if they do genuinely believe you need "help" back into your costume.
One interpretation of the Phone Guy is that he's lying about the sentient robots being murderous to screw with your head. In this case, the guard simply faints from fear if caught and dreams of being mangled. The Phone Guy simply faked his death and recorded backwards audio after the fourth day up until he retired. Humorous, but unlikely, unfortunately.
In the Private Room Ennard implies that Eggs wants to see "her" again, most likely referring to his dead sister who was eaten by Baby, and believes she's still alive as Baby and thus, wants to keep her as near him as possible. This could be a reason why in the Fake Ending, he may have brought Ennard home with him, since they might have his sister in there.
Audience-Alienating Premise: Despite the massive popularity of the games, there are many other people (especially those who only like watching a Let's Play, as opposed to playing themselves) who will refuse to play them since the challenge can be edited down to being "Jump Scare: The Video Game".
Base-Breaking Character: Foxy. Either you love/like him as a normal animatronic, or you hate him for constantly overshadowing all the other animatronics.
Breather Level: Any custom night if you set the animatronics's AI to low.
Complete Monster: The Purple Man, also known as William Afton, is the man responsible for all the horror in the series. A Serial Killer, he murdered eleven children and trapped their souls within the animatronics, turning them into bloodthirsty, revenge-seeking monstrosities. In Sister Location, he is revealed to be the CEO of Afton Robotics, a position he used to create animatronics to abduct and murder children. Sending his own son, Michael to his painful death, the boy returns from the dead to suffer as a revenge-driven spirit. He also planned to corrupt his daughter into becoming a killer herself and, after hisown death, returns as Springtrap, eager to keep killing.
The novels have Afton as well. See here for details.
Critical Dissonance: Five Nights at Freddy's may be the poster child for this trope. All the games but the first have mixed reactions from critics, with 4 being the lowest-rated out of all of them (the same game that has a 96% user score on its Steam page), while fans usually love the whole series with mixes of Broken Base from time to time.
Out of all the robots, Foxy is the most likely to be seen as not actively hostile to the security guard. Some people think he might just be trying to run away from the other robots, or even help the guard. It's probably because he's the only one who doesn't trigger a Jump Scare when he enters the room, though your heart might skip a beat if you see he's out of the Pirate Cove.
All of the animatronics. They're killer animatronics out for your head, and people write fanfictions where they're FRIENDLY to the security guards. This is justified a little since the animatronics are haunted, malfunctioning, or both.
Somehow, even the Purple Man is getting this treatment. Some people draw him as being extremely attractive, and a few have even glossed over the fact that he murdered 5 children.
Enjoy the Story, Skip the Game: The series has attracted a number of fans who are interested in the premise and story, but are turned off by the actual gameplay and content themselves with reading wikis and watching YouTube videos about it instead.
If you haven't guessed from the name: Foxy is a fox. But a handful of people will call him a wolf, coyote, or some other canine.
Some fans won't take kindly to calling Bonnie a girl.
Fanfic Fuel: More like WMG Fuel, but this also applies. The series's backstory and the information given across the whole series ranges from making sense but lacking completeness (like the fact that the murderer even exists) to being completely vague (such as his motivations or personality), and there's tons of room for personal interpretations and or opinions about the events that transpired.
A popular opinion prior to the sequel was that Foxy was the one who caused the Bite of '87, due to his area being closed off and Foxy being less maintained and worn out than the rest of the mascots. Putting 1987 as the difficulty on the 7th Night after a patch, however, brings a Golden Freddy Jump Scare, leading people to suspect that maybe Foxy was a Red Herring. The sequel largely Jossed this, however, since Foxy would've most likely been lying in the Parts/Service room at the time of the Bite.
Fans often portray the robots with an Electronic Speech Impediment of some kind, despite there being little to no indication of that happening in the game itself. However, this is somewhat believable due to how worn and old the animatronics are said to be.
While in canon it only appears on her bib, "let's eat!" is often used as Chica's Catchphrase in fanworks.
Going back to Foxy, there's generally two interpretations of Foxy's role in the daytime show. One: He's an adventurous story teller that provides entertainment when the band needs a break for maintenance or something. Two: He's the villain of the "story" who, much like the Hamburglar, raids and plunders pizza from the Fazbear group.
There are a few consensuses as to how the unvoiced characters would sound like. For example, Freddy's typically depicted as sounding like a Southern Gentleman.
With Daredevil as both series features a purple man as a villain.
Genius Bonus: Bit unclear on how intentional this was, but anyone familiar with opera will recognize the tune Freddy plays is fromCarmen. The subject of said song? A man singing about how much he loves his job, which as a toreador is evading and battling large creatures* bullsthat are trying to kill him. Likely to be very intentional, given the chorus (the only part of the song Freddy plays) is about how the toreador should think of the dark eye watching from above. And that love is waiting for him...
Heartwarming in Hindsight: The message "These characters will live on. In the hearts of kids, these characters will live on." is meant to inspire Fridge Horror in players. However, it becomes oddly sweet when one considers the significant Periphery Demographic of kids that enjoy the game. Freddy Fazbear and his friends will live on in their hearts.
Back in 2004, there was already a pirate captain named Foxy the Silver Fox and his crew the Foxy Pirates.
Freddy Fazbear is a bear who is a Friend to All Children and has a group that all the kids love. Freddy and his crew live in a facility designed for kids where they spend their days entertaining the children while they play around for the day. But, when it's closed during night time, Freddy and the others show off their true colors and their hidden malicious intents. Gee, sounds a lot like Lotso and his gang, doesn't it?
The Gravity Falls episode "Soos and the Real Girl" pretty much features possessed murderous animatronics at a pizzeria, taken over by a female entity no lessnote Given that Freddy's own vocalisations are the slowed down giggle of a girl.... Of course, given the Animation Lead Time, and the very short span of time between the releases of either, it's unlikely there was any intentional similarities.
The yellow puppet chick, Chica, from the children's show "The Chica Show" and "The Sunny Side Up Show" airing on Sprout. It's not known if Scott took inspiration from the show, but the similarities standing as far as the name, species, and occupation entertaining children are just creepy.
The Gamer minigame from Game & Wario, which came out a year and a half before this game. It involves you protecting yourself from an enemy (9-volt's mother, 5-volt) by paying attention to where she is while having a limited energy meter to do so (running out causes you to fail). Sound familiar?
"I am Furious Yellow" has a Show Within a Show, "Danger Dog," and the mayor of Danger Dog's town looks a lot like a bulldog version of Freddy, down to his big eyes and top hat.
In "Flaming Moe", there's a pizza/game place with a sign on it that says, "Kidnapping was at our other location." Not quite a murder, but the gist is the same. Especially when 2 revealed the Missing Children Incident did take place in another location from the first game.
The image quote for Video-Game Movies Suck was once about how that Five Nights at Freddy's movie probably wasn't such a good idea. It was soon changed after a movie really was announced.
Regular Show featured the Capicola Gang, a trio of living animatronics consisting of two male bears and a female duck. (Chica is a chicken, but is commonly mistaken for a duck.) The leader is a bear who plays a guitar that looks a lot like the one played by Bonnie the Bunny. In both of their appearances, the Capicola Gang tries to kill the heroes (albeit with guns). Also, in their second appearance, they are all in a state of disrepair, complete with exposed endoskeleton. Just like Freddy and his crew in FNaF2!
In their second appearance, the bear leader says he never went to school (even though he's a robot). Kind of reminds one of how the FNaF animatronics are possessed by the souls of dead children, doesn't it? Additionally, the bear leader's Catchphrase is "Show folks a fun time!" Come 2016, and we now have an animatronic bear named Funtime Freddy!
In a far darker example, the episode "Broken" from CSI: Miami featured a pedophilic Serial Killer as a villain, who would kidnap children from places like pizzerias while impersonating an employee. His choice of victim and location can remind some of the Purple Man's M.O. of murdering children while dressed as a mascot.
Hype Backlash: The massive YouTube exposure has predictably resulted in people becoming sick of the game and probing its weaknesses and plot issues. Then there are those who look at the fanbase gushing over the game and start from there. And on Reddit, there is a vast majority who despise the area of the fandom occupied by kids.
It's Popular, Now It Sucks!: FNAF is so popular, several channels are doing more FNAF-based content due to its popularity, which makes several of their fans mad.
Not just that, this song is criticized just for becoming popular due to a popular FNAF fan video.
Like You Would Really Do It: Soon after the teaser for FNAF 6 was released, Scott Cawthon said the main series has been cancelled because he wants to focus on other projects, or even do another FNAF spin-off. Due to Scott's Trolling Creator tendencies, many fans don't buy this bit of news.
Love to Hate: In the same vein as Pyramid Head. The bots are surprisingly well-liked for a bunch of haunted killdroids. Fanon often gives them a lot of personality, and most fans seem to accept they act like squabbling but ultimately loving siblings. When the sequel was first announced and it seemed like the old Fazbear gang would be left to rot, it was a Tear Jerker for most fans. As it turned out, they were left to rot in the past, then fixed up for this game.
The fan. Explanation The fan that appears in your room appears in every game for some reason. This got to the point where people made jokes about how the fan is the one being referred to in the Five Nights at Freddy's 3 trailer and Mat Pat saying And more fan. (shudders)
;) Explanation Scott often uses this emoticon in most comments and replies he makes, usually in a teasing sort of way. This has mutated to a point where you can actually use this emoticon as a flair on the FNaF subreddit.
Mis-blamed: On the official FNAF subreddit, Rebornica is blamed for many of the problems they caused by their AU. However, many people forget that Rebornica's violent reactions were due to the massive flow of bullying that they received each day, that they were unable to stop their character, Vincent, from being turned into an abomination by the Vocal Minority, that their fandom got out of control and became annoyingly pushy, and Rebornica has repeatedly insisted that their comics are an AU, NOT CANON. Still, though, you shouldn't mention this to any Redditors, unless you want to get downvoted to hell and back.
Thankfully, the subreddit has actually begun to realise their misblaming towards Rebs.
Moral Event Horizon: The killer crossed it by killing five children and letting someone else get arrested for the deed.
Never Live It Down: The insanely dangerous nature of the job that most of the player characters take has elevated into a running joke that was eventually even referenced in Sister Location with a character questioning whether you have a death wish. The thing is, in a sort of reverse Survivorship Bias, the player character actually would have no reason to believe they're actually in that much danger in any situation in which they survive the night (read: the only times they'll come back to the job the next day). The Arbitrary Skepticism that they're stereotyped with is only such to the player because they see timelines in which the character dies (and the minigames revealing more of the history of the locations). The character themselves has no reason to believe they're in a horror game or that there's anything supernatural going on any time they survive a night, so it would just be a really unsettling job to have, not a life-threatening one. It still wouldn't be everyone's cup of tea, but it wouldn't require a death wish to stay in. The closest exception would be the final night of the first game, which takes place the day after a phone call that heavily implies your co-worker was killed. However, even then, from a real life perspective, you'd likely expect that your co-worker is playing a prank on you (even, if not especially, with the scary but random message on the next night), since possessed killer animatronics don't exist in real life, and you haven't seen them do anything more than wander around in a way you're told is part of their programming.
Popular with Furries: The series proved appealing to many furries, despite not exactly being a horror furry game. Especially Foxy. Someone must have taken notice, as at least one prominent furry site, FurAffinity, now runs ads for the game.
Some theorize the player character is actually the man in the Freddy costume who murdered the children in the backstory, taking a job at Freddy's to make sure the truth never gets out, and if the animatronics are in fact possessed by the kids he murdered, it makes a lot more sense why they want him either dead, or to become what they became because of him.
"Seinfeld" Is Unfunny: When the first game was released, it was seen as innovative and unique, with its simple but compelling gameplay style and presentation never seen in any other horror video game, which helped to make it popular. But no less than three sequels with little to no variation in the basic gameplay released mere months one after another, and countless of clones later, it lost its uniqueness and a lot of people got tired of the franchise. Nowadays, few wants to look back at the first game or any of its sequels, and practically only the biggest fans of the franchise and horror games amateurs continues to care about the series.
All of the animatronics can fall under this. Especially Foxy.
Possibly the reason for Foxy's popularity. After you get over the initial Jump Scare, his half-closed eyes and slack-jawed expression are almost goofy. The fact that he merely steps into the office rather than lunging at the player also detracts from the creepy factor.
Deliberately invoked with Freddy and co. The creepy CG on the suits makes Freddy and his friends seem off-putting and extremely scary. The genesis for the games came from Scott Cawthorn's previous efforts being criticized for having characters that moved like animatronic puppets. He almost gave up on game design before realizing "Wait, I can use that..."
The Greenlight trailer features Bonnie pulling off his mask/face to leer at you with his metal endoskeleton, apparently just to be creepy.
Viewer Gender Confusion: Bonnie and Foxy in particular fall under this. On the one hand, they are referred to as male in games (IE: Phone Guy states that Foxy hides behind a curtain because "He doesn't like being watched"). Likewise, both have a masculine appearance to them (Bonnie being muscular and wearing a red bowtie and Foxy being dressed like a typical pirate (eyepatch and hook hand)). On the other hand, both Bonnie and Foxy are names often associated with females. It also doesn't help that these are robots we're talking about, which wouldn't really have any clear sex/gender to begin with. Because of this, there is a lot of debate among fans of the game as to whether or not Foxy and/or Bonnie are male or female or if it even matters.
Word of God has confirmed that Foxy and Bonnie are indeed males. Though that hasn't stopped fanart of them being portrayed as females.
Likewise, Chica tends to be mistaken for male by first time players, due to her not having many Tertiary Sexual Characteristics. The second game gives her Toy counterpart a more obviously feminine appearance.
Viewer Species Confusion: At first, many mistook Chica for a duck (and many still do), but the general consensus is that she's a chicken. Also, some mistook Foxy for a coyote or a wolf at first.
What Do You Mean, It's Not for Kids?: Children's animatronics in a family pizzeria as you do night watch! What could possibly go wrong? Well, if anyone paid about fifteen seconds of attention to the Greenlight/Steam trailer, everything.
Conversely, What Do You Mean, It's for Kids? in that a lot of children really love the games, they're actively play tested by Scott's own children, and a lot of merchandise is aimed at kids as well.
Win the Crowd: Regarding the movie. The announcement that the animatronics will be brought to life with genuine animatronics and practical effects, and that Scott Cawthon will be heavily involved in the creative process (and director Gil Kenan implying he's perfectly happy to have Cawthon reprise his role as Phone Guy) have alleviated many fears about the coming adaptation.