re: Why do people post?
I say, let them post. They really believe they are demolishing their critics with wit, but they are only showing themselves to be cowards and bullies, and hurting their own cause by alienating those who are uncommitted, or even potential allies who are more gentlemanly than they.
I once asked a friend, a committed Marxist, why he hadn't joined the Party when he went to college at Columbia in the late '60s. His answer was right on target, and applicable to this forum: "I agreed with their politics, but they were all assholes."