This is all too common, for me to see. I see people hate entire franchises simply because of popularity. There are probably several reasons for this, stuff relating to overexposure. But just because something you've seen doesn't live up to the expectations set by the community surrounding it make it worse than Hitler. People hate MLP because of the unexpected male demographic rather than the actual show. People hate Minions because of the marketing and spread by a bunch of old parents on facebook rather than the movie itself (which also isn't worse than Hitler). And people hate FNaF because of it's popularity despite being a cheap but pretty decent jumpscare simulator. Now there are people who have more legitimate reasons to not like these franchises like FNaF only being good at jumpscares and Minions being mediocre of course. I want to know why people aren't as fair when these kinds of franchises get so popular.
Oversaturation can lead to immense hatred.
On this website for example there is often times floods of Jojo or Steven Universe stuff and when you come to the website to see "funny meme pictures" and all you see is a constant stream of something you don't care about you start to get resentful towards that thing.
MLP is hated on because it's fans have been and are known too bring it into everything. They turn everything into a pony version and will spread them while I feel the hate has died down as the internet moved onto a new thing to hate on it still exists.
Minions are hated on because they are fucking EVERYWHERE. they are using entirely as a marketing gimmick and when people try to escape to the internet where they can avoid ads they get spammed by people on social media using them as a joke. It also doesn't help that so many animated movies feel they need to rip off or have a clone of the minions now so they can whore them out to advertisers.
Overall people hate popular things because they feel they are surrounded by it and slowly grow to hate it if they have no interest in it. I had no interests in the Final Fantasy games (never owned any and didn't stick with the PS2 for long) so when I grew up hearing other people constantly talk about how they are some of the greatest RPGs of all time and how everyone should have to play them, I started to grow to hate Final Fantasy. Now after I got away from all the people who would constantly glorify these games and tried a few out myself I thought they weren't half bad, but still I probably didn't enjoy them as much as I had this natural hatred that kept bubbling up making all my nitpicks seem like bigger issues than they were.
Just human nature I suppose. People want to experience new things and see things they want to see not things they don't care about or don't like.
Special Snowflakeness, Hipsterism, (Both stemming from a desire to stand out from the so-called "sheeple") Edginess and everything Basillius said
You'll get VERY annoyed by something when it is surrounding you on every angle.
The REAL question is; why are people so public about it?
You see, being annoyed into hatred is easy and understandable. It is a huge reason why people hate Ponies, FNaF, Minions, Furries, Social Justice, Ironic Humor-- the list could go on for a mile, but Basillius explains it pretty well above, so you might as well read that; the point is, people need to learn to keep it to themselves.
Hating something because it is all over the place is like a bland Facebook post; it has no reason for being public. Yet people still put it out there. Is it because they think they're fighting it by being public about it? I dunno, it's still stupid as shit to just splurge it all over the place and make yourself look idiotic.
Overall people hate things for their popularity for pretty understandable (Often petty, but understandable) reasons. The point is there should be no damn reason why it should be tirade and flamewar worthy yet people act like it is… Either ignore the shit, vent your complaints to a good listener, or something, but it is damn better than wasting your time posting it all over the place like a bratty kid who thinks he is always right.
Because of Kool-aid.
It's a force of nature. Yin vs Yang. All things popular must be countered by an equal and opposite antipopularity.
Basilus outlined why this is fairly well. Basically the more exposed something is, the more people will get tired of seeing it and eventually people start to reject it.
Similarly when something is touted to be greater than it actually is, the people who don't buy the hype will actively try to tear it down to it's proper level.
The sense of being surrounded by it, and the precieved threat that this saturation somehow threatens the less popular thing you like, or in some way marks you as inferior to others, is probably a major reason.
But I think there's more to it then that, after all, there were plenty of people who liked certain things, but grew to hate it the more popular it got.
I think the audience that are attracted to the growing popular stuff make some people hate something popular. A more mainstream audience, a less serious or hardcore audience, dare I say an audience that doesn't really care to look deep and just see something neat to watch for a couple of minutes. There's a stigma about the mainstream that they're idiots, that anyone who likes anything mainstream is a moron who drolls in public and likes Micheal Bay films and Adam Sandler movies. They tend to not really care about the deeper meanings of the thing they like, and instead just enjoy it for the simple reason of "I like it" or "its good".
This can drive some people crazy when the majority of people they run into aren't hardcores willing to make paragraph long discussions about some side character or participate in a thread about a fan theory or debunking a fan theory. It makes them think that the fanbase and thus the product of said fanbases attention, has become more simple, and thus closer to the aforementioned Micheal Bay Adam Sandler quality. They abandon it and treat it like it were that, because in their mind it is.
Never mind that people like things in different ways, and that an audience doesn't usually change the quality of a product in question.
People hate popular things because they don't want to keep looking at them.
TL;DR this thread, It gets annoying.
How are you supposed to call yourself an "eccentric intellectual" if you like the same things as "average people"? People pretending to be intellectuals would never like something popular (even if they liked it they wouldn't admit it or they would say that they like it for "other reasons than most people").
PS: Note that I said "People pretending to be intellectuals" and not just "Intellectuals".
Also, if you genuinely hate thing thing, as in you tried it and didn't like it and/or hate the concept of, or it maybe even offended you, that's really gonna grind your gears when people start constantly go on about it.
Especially the most annoying part are the obnoxious fans, they might take something you hate and then try push it into something you really like such as the bronies that ponify everything.
Hell even if you like something, the popularity may bring in fans that you find unbearable, making not really want to talk about because you run the risk of running into some overly obsessed 12 year old or neckbeard that, essentially, just likes the same thing in a different way (like creating fanfics and fanart).
A good example is Minecraft. Lots of people fell out of it because its now associated with young children, neckbeards, shitty Lets Plays and even straight up autism. This only means that because more people who don't have these negative stereotypes are leave the communities or games etc, a higher percentage of the fans become that stereotype and it perpetuates the cycle.
As others point out, the koolaid point is the main reason: over-saturation leads to disgust. I also think there's an element of people who dislike a thing's popularity because they want it to remain a cult following, like small and personable rather than vast and widely-received. So think book club vs book conventions, a lot of people like cons but most would rather just have a personal thing that doesn't go beyond a close circle of people.
Things like this:
Ignoring the shitstorm of politics behind the image itself, people hate overly popular things because they start getting appropriated for every little thing of increasingly tenuous relation to the source material (be they political assertions, cancerous memes, toys, unasked for products etc.).
People also can dislike popular things due to the fanbases themselves, perceiving these large groups as having annoying "up-in-your-face" attitudes (common criticisms of the MLP and PewDiePie fandoms)
As mentioned above it can be a case of literal oversaturation, you have too much of something to quickly and you begin to dislike it.