It's sort of funny. In almost every other aspect of physical beauty, rarity is prized. Blonde hair trumps most hair colors because it's relatively rare. Blue eye color trump most eye colors because it's so rare. Light/white skin trumps darker skin (and I'm talking globally, not just with black folk) because it's relatively rare, compared to dark skin.
But one of the few things we have that could be consider rare, the one thing that bascially only people closely descended from Africa (and it's geographical environs) have: our kinky-curly-wooly-hair--it seems to be the only rare beauty trait few people prize. Even worse, it's sometimes reviled.