I'm sorry to point this out, but myself, like millions of Americans have been brought up seeing "The Wizard Of Oz" countless times, just like "Star Wars" or anything legendary. And it turns out that we all have seen a white Glinda. I happen to be very attracted to black people, so I can promise that this is not a case of rasism, it's moreso a case of a predomanatly white audience not knowing why someone they've seen since their early years looking "different". Yeah, it sucks, but it's the truth. (And hey, on the bright side, atleast a black Glinda could marry a white Fiero! Not so much luck for Fiero and Boq...) So calm down, and realize that it's not racism, it's money.
If Lincoln were alive today, do you think he'd be pleased with his tunnel?