Humans are not logical creatures with feelings. We are emotional animals with the ability to rationalize. Forget your fantasies and focus on reality. Racism is a core part of what makes humans human, and those who lack it will be replaced by those who do.
Sure, we aren't robots (thankfully) but if you're not indoctrinated in a vulnerable phase when your mind is still in formation, that is, during childhood, you probably won't blow yourself up because a fantasy book says that you'll get 7 (77?) virgins at your disposal if you kill "infidels".
From a group-competitive perspective, it makes perfect sense. One of theirs for a dozen or more of ours is a good deal, evolutionary speaking.