I do, as I imagine others do too, send a few messages to services/gambling sites offering my service as a Campaign Manager and asking them if they'd like to give it a go here at the forum.
You're sending unsolicited messages advertising your service to people. That counts as PM ad spam in my opinion.
This is going to hurt a lot of forum members who are in your signature campaigns.
He can still make payments and do post counting while banned. He would just be unable to post the payment transaction on the thread.