I understand this site pretty well. People come here with their brains turned off, only being able to think of each other and the world in form of derogatory or otherwise simplified stereotypes. The social inhibition is dropped and interaction takes place on the basis of reacting to short-lived lower impulses, like entertainment, amusement and sometimes even thinking of quick cunning jokes and arguments. The complexity of the social and moral system only goes so far as it doesn't immediately interfere with the current emotional inclination or with conditioned responses and it doesn't violate the self-image. People may still bring their personal interest and topics into play, which they might even be obsessive about.
It is like a vacation from reality. I can understand how you can think of this as not being trolling or to some extend even normal. But it is just so exaggerated here, you can't really draw that distinction much.
Some might not realize what is going on and some might actually believe in it. That is the frightening part. You can't be sure who actually didn't leave their brains at the door.