It's almost impossible to keep VIP by reviews alone.  I think CCs are the best way of paying.  Some prepaid cards have been used but as fast as one that works is uncovered, there are reports of the not working.

Never had a problem. I kind of miss the old days when we could pay by money order made out to Warped Monkey.

There is the legal aspect, but there is also the social aspect of having your name and CC number associated with a site most people outside the hobbying community would likely frown upon.  

For instance-

Wife: "Hey honey, what's this recurring monthly charge on our CC for TheEroticReview?"  

You: "Well, uh, see...."