I think it's also the fact that internet culture encourages mass dumbing down and stupidity, while simultaneously catering towards the arrogant, "I'm sooo sophisticated" crowd who think they're amazing.
Both types of people are irritating to deal with.
Take your typical "memes" for example. They start off funny or witty sometimes, but often evolve towards people thinking they're "oh-so-clever" for using them in an offensive or stupid way even once the whole thing has been done to death.
That whole conformity-of-attitude really appeals to immature 12 year old kids and the like. I remember back in secondary school that I'd hear someone shout "Owned!", "Fail!" or reference some meme in real life about 500 times a day.