Yeah, its a crime to buy, not a crime to sell (to protect those who are forced to sell sex/trafficking victims and enable them to turn to the authorities without risk of repercussion).

While it's not legal to commit fraud, you cant use the justice system to get your money back since transferring that money for sex was a crime. It would be like going to the police and complain about someone in your money laundry business is stealing money.

So basically, if you're a creep you're pretty screwed(no pun intended) if the person selling sex isn't really up to it after you've paid.