I didn't read every post on this thread so don't bitchslap me if I'm repeating something
Giving away your CC is not going to work since hardly anybody would give away a CC and making them pay to post is not the way.
I think if you run a serious business you can get a bot that will detect most cheaters.
Most of the bigger tgp owners make some nice money so the problem of cheaters is part of the job but they suck for sure.
I think the best way to scare cheaters off some is indeed talk with their sponsor so their account will be deleted and if they don't the sponsor could get banned.
Plus requiring the submitter to leave his phonenumber before he is allowed to submit is a cool idea. sublime does it and I think it works quite well but limitting the number of submitters is not real cool since you should give newbees a change as well.