Just a proposal..
To avoid so much no needed posts. Maybe it is worth to control signature campaigns?
Most of bounties require about 10-15 posts a week, not really understand why so much is needed.
If this number will be reduced to, for example, 5. It will reduce number of not needed posts at least 2 times!
In my opinion, the more posts you need in advertising campaigns, the more mess and spam you get. If you have something wise and good to pass on to other forum users, just 2-3 posts per week is enough.Looking from the advertiser who wants to see as many people as possible, the client requires a large number of posts. Here you will write something in this topic, you will write something and make spam everyone will write anything so that the week will be credited
If the problem is posting from the signature campaign, why is there no limit to the bounty program? and participants to follow it. I think by implementing such a rule it will be more effective in cutting off posts that are not qualified. In addition, there must be a bounty due diligence because currently the problem is the fraud behind the program.