And registration isn't closed to anyone. So that argument won't stand.
Some people just don't care enough or actively avoid this forum.
Chatbox, you can take a screenshot and PM a mod/admin. Haven't gotten one from you yet.
Because I don't care about people talking about others.
Blogs, you can report those as well. Haven't seen a reported blog from you either.
Because I don't care about blogs in general, I find them amazingly attention whorey.
Private Messages well, me personally I consider those like an AIM conversation. We aren't out here encouraging people to harass and stalk other posters via private messages though, they have a different function.
So why aren't social groups just considered mass AIM conversations then? They're private in that you need to be invited to them, in the same way private messages are private because you aren't listed in the send field.