Why can't we all accept others feelings ?
Why can't we all accept people are born into many situations that differ ?
Why can't we all learn to love and accept others as they are ?
I disagree with all the people who segregate cause of the way people are. I love Lady Gaga for her newer song Born This Way cause in it she sends a message that screams "Hey. We ain't all the same. Some are born black, some white, some were born gay some straight, et cetera." so why after all this are people still so sickening ?
I'd say because the real or artificially upheld scarcity of resources. The fewer the available resources are, the more people we percieve as competitors.
Also, indoctrination plays a big role just like the divisive power of religion. And maybe because our brain can't handle a social circle wider than 150-200 people (this is the number of hunter-gatherer groups humans used to live in in the pre-neolithic age).
Anyway, I can imagine a better society where people accept eachother more and cooperate better, but I don't think it will ever be realized.