Aye, misanthropy is just extreme pessimism carried to its logical end. The belief that everyone will betray you if given half a chance is a way of looking at the world where the misanthrope is usually the only victim... and at least it's fair.
Also, people who just generally hate everyone tend to realize that the title of Universal Overlord is beyond their grasp and thus not actually harm anyone... there's no point, as no amount of fighting or dirty pool will rid them of the scourge of humanity. On the other hand, people who are racist (especially in places where the hated groups are vastly outnumbered) often do take matters into their own hands... whether it be by tying someone to the back of their car or by refusing to hire people of a certain skin color.
Dexiro said:
I think a better question would be why aren't all prejudices treated equally.
It's not ok to be sexist or racist but it is ok to be homophobic? Not cool brah.
Unfortunately, some prejudices are still more common that others, and better supported in religious texts. It's changing, though. The tide is turning, and more and more good Christian people are starting to look at those passages the way mainstream Mulims are looking at those passages about Holy War... with distaste and sincere backpedaling. This is all to the good.
Of course, I was raised to believe that what was true is true and will be true, so instead of backpedaling I'm forced to accept that something isn't true anymore then we were obviously wrong about it all along... and therefore everything else we took as infallible isn't. Leaves me a bit adrift at the moment to be honest, but that's a different conversation.