The stereotypical hipster is a myth. There's no subculture of people who are arrogant, pretentious douchebags. The term is used broadly and pointlessly to describe anyone whose views differ from that of the user, and has the nerve to defend their views. It's entirely subjective, in no small part due to the fact that "mainstream" is also subjective.
The problem is that large swaths of perfectly good culture and ideas have become somehow associated with being a hipster, which is always seen as a bad thing. Not everyone who could be described as such is arrogant and pretentious, of course--whatever group you associate yourself with does not define your personality.
So we have normal people who simply have different tastes from whatever the established mainstream currently is (which changes just as much as the current trends) labeled as douchebags by virtue of not liking the same things as some other people, who may not even be the majority.
Now I may be a little biased because I live in Portland, which the rest of the world seems to believe is 95% hipsters. I'm okay with that, because what I see is 95% normal people with a variety of tastes and ideals. Some of you would probably consider me a hipster. Oh well. I don't lord it over people, and neither does the majority of the "hipster" population.
It's a surprisingly meaningless term, when you actually stop to think about it.