It's weird that there's no better (random) trait to distinguish "races" than skin color. How about hair color? Eye color? Shoe size? Amount of nose hair? Skin color doesn't define races, just like the other things I listed don't.
So there's gotta be other reasons for those people to rage against other "races" than just one thing about them being different, but since I don't want to simulate getting into their minds, I won't speculate about that now.
If it is a high amount, I am in this club for sure...
There are lots of reasons, but how many of them are real reasons?
None!