Hipster-hate strikes me as just another thinly veiled form of bullying, and it's interesting to see how readily internet nerds - the people who are disproportionately to have been bullied in the past - engage in it. Look! He's different! Let's make assumptions about his motivations and get him! It's also interesting to see how many times Reddit (and other communities) fly into a rage-fest because of lack of context,…
My theory has been that the downtrodden are pissed because they're on the receiving end, not because it's wrong, evidenced by many examples of them engaging in the same behavior when the opportunity presents itself. Whether it's immigrant minorities or geeks/nerds, the pattern seems to come up time and again.