I am not aware of any other forum in which the mass collection of posts are allowed.
Lol, please define
forum. A collections of
posts, maybe? All publicly accessible posts?

I think this just became number one on
QuickSeller's List of Asinine Accusations.
Posts made in the forum are visible for all, excludes special boards for staffs and VIP members (as far as I know). Everyone have rights to use quote button to quote posts and they can save, scrap, archive any post they want.
If one care about their privacy, just don't use public forum or don't post personal information publicly.
As I read from the Welcome message by theymos, the forum is a place for discussion, not private or secret discussion.
This forum exists to provide a platform for the free (but ordered) exchange of ideas. If you have an idea to express, then it is probably possible to do it here as long as you follow the rules.