Hmmm.... as far as I know, there are havesting bots that automatically search internet pages for email addresses. They don't have to be members of this board to do this. As long as the pages are crawlable, they will get your email... It's wrong of those spammers to do so, no doubt, but I don't think it has anything to do with the board per se.

If it's a spammer that promotes paysites and spams me, in any email address, I usually report them to the sponsor. None of the major sponsors allow spam, and it leads to the spammer's account being shut down.