While I'd normally have just have thrown this encounter in my ever-expanding "Fuck vegans, amirite?" pile, there was something about this particular guy that made me realize for the first time (I am not a very smart man) that this kind of obnoxious behavior is less about the school of dieting a person buys into and a lot more about the person himself. The reason people like me think vegans are punchable dickholes isn't veganism itself; it's the relatively small percentage of preachy assholes within the movement. I call this specific brand of jerkwad the Obnoxious Fanatic, and he/she pops up in each and every phenomenon, trend, and philosophy as reliably as Rule 34.
You don't hate hipsters because of the hobo-looking folks minding their own business at the corner of a cafe in Williamsburg -- you hate them because of those couple of Pabst-drunk fuckers you once met at a party, peacocking their sailor tattoos and actively condescending to everyone. You don't treat yoga suspiciously because of the discipline itself; it's because of that one co-worker who keeps sending you links to her blog, "Yogifreek," whose every post ends with the word "Namaste" and features copious amounts of yoga pants buttcrack. The Obnoxious Fanatics worm their way into everything and bang their drum in every direction. Because of them, our general attitude towards most trends can be summed up by a joke I once heard: "A CrossFit trainer, a gluten-free dude, and an atheist walked into a bar. We know this because they told everyone."
And that's the point, really. Unless you're into, I don't know, animal mutilation or Gamergate or something, chances are the vast majority of humanity is completely cool with your little hobby/philosophy/passion. Where you rank on the official Poisuo Asshole Scale highly depends on how little you can shut up about it.
Ryan McVay/Photodisc/Getty Images
It can also be used to measure actual assholes, usually right before I force the metaphorical ones to climb in.