As with just about everything, the original hipsters of the trucker hats were non-conformist. There was a certain risk of ridicule they were taking for being hipsters in, what, 1998? Now, however, there's absolutely no risk to being a hipster. It's not a counter cultural movement, they're not objecting to anything worth objecting to, and they're not going out on any kind of limb. At this point it's just a kind of lame, conformism wishing that it weren't.