There's a post about authenticity at Thread for Thought that links lots of topics-- hipsters, Native Americans who reclaim imagery, drag queens, Marie Antoinette, the ongoing hip-hop baggy-pants legislative battles, French ladies' hats during German occupation.
Much has been written about dominant cultures appropriating oppressed cultures. Fashion trends like the current "tribal" and "ikat" trends take various cultural elements and re-sell them to Westerners with no context of meaning or history, flippantly turning those idioms into Western ones. Some Native Americans, for instance, reclaim images of old Hollywood cowboys & Indians like feathered headdresses because those images have been appropriated and twisted by an oppressive dominant culture. To put it another way, hip hop culture has also been appropriated to some extent by powerful corporations and white pop culture. Dance moves, phrases, beats and clothes "borrowed from," (but never returned to) hip hop street style have left a sour taste for many people of color who consider themselves a part of that culture.
I think this is a small part of why so many people are angry with hipsters. Hipsters appropriate from everywhere. They're in hot water with cultural studies departments right now for wearing feathered headdresses, championing "ironic racism," and for fetishizing oppressive masculinity. I think part of the reason they do it stems from simple retro styles being back in. The '70s are in, and in the '70s the dominant culture appropriated massively from Native Americans and other cultures.
But hipsters also appropriate from dominant cultures. Anchorman mustaches; unwieldy glasses which, still today, can be seen on white-collar workers and nerds alike; a nostalgia for the '80s that was popularized by Gen-X-ers who glorified their own childhood, but is now seen from people born in the '90s. Lodge/sportsclub decorations and aesthetics, European bicycle culture, white "trailor trash"-y styles. The implication is, all those cultures exist for hipsters to play around with. It implies that those dominant cultures don't know any better because they're older and stodgier, but hipsters are young and playful so they're doing it ironically. For many people from dominant cultures in the U.S., this is the first time they've experienced having their culture appropriated and twisted.
I definitely don't want to compare appropriation of cultures by their oppressors to dominant cultural appropriation by hipsters. First off, hipsters aren't dominant. It's not like aging geeks and good-ole-boy hunting clubs don't have a mouthpiece with which to object. Second, I don't think it's really hurting anyone, just sort of mystifying them and pissing them off. I bring it up because I want to note that the attitude has changed and expanded about what's up for grabs, and that's a new feeling for a lot of people.
What does this have to do with portraiture? Mmmm-- something, I'm sure.