I was just answering your question from my personal perspective, and i can't pretend to truly understand what motivates people to hatred and bigotry, but I think many people are scared of things they don't understand and things that are different - it's universal, from picking on the fat kid, or the black kid, or the kid with glasses, or the kid from the poor estate in the school yard, to race riots and suicide bombings.
experience, familiarity, intellect, a good heart and an open mind help to calm those fears. and then you can look at people for who they are instead of what they are or represent.
If i love you it's because I think you're lovely - take away all the crap and then life and decisionmaking become so much simpler....