I beg to differ. Noone knows who owns what copyright here. I could simply start adding a copyright notice to all my posts to block anyone from reprinting them.

as anyone who posts here already implicitly agreed about the public display of the posts

Public display on this web site, not public display in someone elses commercial venture.

I think that this mindset is a bit too narrow for me

Maybe so. Like I said, I may be in a minority. But if I don't want anyone to make money off my free advice, that is my choice. My advice is free for those using the PerlMonks website to view, not copy and sell.

I'm more into the real "free" aspect of Perl than the GPL "free" aspect obviously

The Perl source and Perl answers aren't the same. The documentation for Perl is copyright by tchrist. You can just print it in a book and sell it without his permission (or at least not without doing the entire thing). You can read my answers for free, but you can't make money off of them for free.

Cheers,
KM