OTOH, I have a feeling that those shitposters in campaigns will invariably find a way to get around whatever restrictions/changes that are imposed, since they still have to meet their post quota (and you know nothing's going to stop them from doing that).
I'm sure there must be a stopped to spammers if they never change and keep making really bad posts especially when a number of posts are reported and deleted by moderators then that user will get a warning. Moderators will ban spamming users especially after a large number of their posts are deleted and moderators usually give them a temporary ban before banning the user permanently.
Campaign Participants:
Staff do not want to hand out bans for unconstructive posts but if we feel that you as a user are continually making very poor or unsubstantial posts due to your paid signature the following bans will be issued:
First offence: 7 days
Second offence: 14 days
Third offence: 30 days
Fourth: Permanent ban
If more and more self-moderation thread remove a large number of spam posts from spammers then it will only reduce spam without any meaningful change to the culprit unless a neutral or negative tag is given (negative tags probably shouldn't be), but by reporting the post then there are two benefits to be had is taken and it is less spam because it is removed and chances of stopping spammers due to temporary ban or permanent ban. But I can totally understand why the OP is starting to worry about the gambling board so far and that's why many merit source will ignore that board.