People that constantly argue over a band's genre.
Joe: Hey man do you like Band X?
Steve: Yeah, Band X is a really cool rock band .
Joe: Oh shit. Sirens. It's the fuckin' genre police!
Steve: Lets get the fuck out of here.
Genre Police #1: WTF!? Band X isn't rock! They're emo!
GP #2: lmfao, nub. they're nu post emo-hop. <3
GP #3: fuk u they r metalcore!21~
GP #1: EMO.
GP #2: <3 nu post emo-hop kthxbai. <3 <3
GP #3: metalcorne1!! bob wot do u think?
Bob: Couldn't care less. Just enjoy the music.