If we're not having fun, then why are we doing it?
These are DISCUSSION boards, not mutual admiration boards. Discussion only occurs when we are willing to hear what others are thinking, regardless of whether it is alignment to our own thoughts.
Most actors and athletes block people because if they didn't block certain people, they would probably snap and punch them in the face, thereby costing them jobs. So I guess, yeah, you could say they block people because of job security.