Both.
It really all boils down to one group of people who believe themselves to be the Master Race.
Animals like you and I do not possess a fully human soul. Our souls are more like those of intelligent animals. That's why it's morally acceptable to predate us.
Nah, nobody really believes that. If you are alive and able to talk or read a few basic symbols, you are too smart to really believe that 1) separate bloodlines exist (obviously they don't) or that 2) it would make any difference if they did (obviously it doesn't).
However, if you are suffering from one of many very common mental illnesses commonly passed on to children via abuse, you might want to pretend that you believe such bullshit because it lets you 1) continue being unhappy and 2) work to make other people unhappy.