On the www.Outdoor-Fishing.com site, where I'm a moderator, only the administrators and/or moderators have the power to block or ban someone from the site. Probably the same here. Who are the moderators on this site? This is their job.
And at Outdoor-Fishing, not only would I have banned this poster from the site, but his foul post
would also have been removed and filed in the archives, where only the administrators and moderators have access to it.