Sarcasm noted. However, there are plenty of places on the web that don't have these kinds of moderation options. Even so, no community is truly open. Each has its own norms, and means of enforcing them.
I try to imagine a post as a cocktail party. If I am hosting the party, the people that are there are those I will tolerate. However, if someone at my party doesn't see the qualities that I do in my old high school buddy, then they shouldn't have to suffer his conversation. But, if my buddy starts getting in people's faces and going on about how the world is ruled by lizard people, or is just being a dick in general, then I'm going to show him to the door. Maybe there will be a house party down the street that will appreciate him more.
Implying the world isn't ruled by lizard people.