One of my credit cards (Citi) allows creating virtual credit card numbers. I've been hesitant to use them in this way, though, because I'm concerned it could affect my credit.

Does anyone know if legally you're on the hook for the paying the service provider? As technically they did provide the service, and you're "refusing" to pay for it. Presumably, if so, they could send the bill to collections and put a black mark on your credit.