Very nice issue raised here Op.

I have to agree and disagree on some of the issues you raised.

• I was an active user in the gambling discussion thread. I am not a gambler but I am a football lover and analyst, that was why I liked the board. Though I posted much there because my first three campaigns were all gambling campaigns (Rollbit, Blackjack and FortuneJack). It is sad that some people that has zero knowledge of the game comfortably drop nonsense and unrelated posts
• I personally feel that updating this thread and calling the users out would be enough punishment.  Then managers would likely visit the thread before accepting users.
• I do not buy the idea of self moderating the topics or locking the threads. The threads give me the idea of how long the forum has been. When I'm less busy I do visit page 5, 6, 20, etc of those 1000+ pages to read what happened then and have fun. I don't wish it should be locked

The best is to report as many as you can and also call out the individuals periodically.