Due to the fact anybody joining to your campaign gets negative tag, it's pretty clear that you cannot attract quality members. While maybe some can easily make 30 quality posts in a day, others may not manage to make even 5 without spamming. So the limits alone, while they can help, they're not necessary useful (because of the quality of members). I will not even go deeper in discussions about the possibility of same person having multiple accounts there.

Also due to the fact reputable members tell that they've had to report huge number of posts for spam means that the managers you have don't do such a good job.