People labeling certain bands a particular genre when it's not. Like labeling Marilyn Manson as Goth when he isn't goth rock or labeling Twenty one Pilots as Emo when they're not emotive hardcore. Emo is a genre from the 1980's DC scene while Goth is a genre from the late 1970's from the Batcave around the United Kingdom. I can have a discussion on what's considered Emo or Goth and what's not, but I'll tell you that Emo and Goth are completely different, but they do have 4 things in common: 1. Both have been bastardised by the media 2. They're both about the music, and not about any fashion (unlike Scene and Lolita) 3. They're both branched off from Punk Rock 4. Lot of elitists and poseurs in those two music scenes.
Another thing that gets me mad is when people try to make one particular aspect (or probably not even what they are) as their whole entire personality. Like somebody can make being cynical their personality, but no one really cares about you being negative. Other things people can make their personality is having a disability, being LGBT, being a war veteran, trying something like marijuana or khat once and brag about it, being a bodybuilder, etc. It just gets irritating at times, and I usually walk away, shake my head, and roll my eyes. It really gets old when that's the only thing they talk about.