The point is, there's a reason these stereotypes exist. There's a good reason that most stereotypes exist -- either that's the way quite a few of the people are, or that's the way that quite a few of the most visible of those people are. Why do people think black people like fried chicken and watermelon? Most black people I've met like fried chicken and watermelon. Is that a negative stereotype? Not really negative, no, but still a stereotype, I suppose. Honestly, most asians I've met are good at math. Most feminists I've met are ugly, hairy-legged man-haters. Does that mean that all blacks eat nothing but fried chicken and watermelon, or that all asians are good at math, or that all feminists are hairy-legged, bra-burning man-haters? Not necessarily. Neither does it mean that all white men are beer-chugging, wife-beating, NASCAR-watching chauvanists, or that all teenagers are thugs and gangsters. These people just have the biggest influence, they're the most visible -- the largest impression of their group comes from the worst of their group. And while stereotypes may not be correct for all members of the group, the reason stereotypes and generalities exist is because they reflect the impression that the most visible members of each specific group give off.

Basically, stereotypes don't reflect every member of the group. You're a member of a group, but nothing like the stereotype? Tough luck kid, it happens. You can either complain about it (and add "whiny" to your group's stereotype) or be an example of somebody that defies the stereotype (and help to wipe out your group's stereotypes).