Miles Thirst is this character that Sprite seems to have invented to shore up sales among young black people and white teenagers. It’s sad when you can look at an advertising campaign and point out its motivation like that, but it’s so painfully obvious. Now, here’s the thing: it’s not just the weird, very white-suburban praise of hip-hop that seems to offensive to me — “If lovin’ hip-hop is wrong, I don’t wanna be right!” — nor the obvious patronizing that goes along with such a statement made, after all, with a big SPRITE sign in the background… ie. Is …