I am going to add my 2 cents in, because I don't think this has been highlighted. When others have said it’s a paper trail, it’s a serious paper trail....
When you establish a merchant account for accepting credit cards you have to state what the nature of your business is. They have thousands of codes that define what these are: farmer, firearms manufacturer, health club, etc. Adult entertainment establishment is one of the codes. I guess that is what would be used. The banks routinely monitor the transactions, and if they see anything they don't like, they hand it all over to the FBI. The FBI will be able to easily identify that it’s not really an Adult entertainment establishment. This is wire fraud, it's basically when you transfer money electronically under false pretenses. It's a federal felony, the penalties are severe, and it's investigated by the FBI, so you don't want anything to do with it. Lots of things can trigger the investigation, like if you do a transaction with someone who later gets caught for being a drug dealer. The reality is that agencies, and providers are small fries, so they probably wouldn’t take much notice, and they probably get away with it. Also, this information applies to merchant accounts who get a POS terminal, there might be other ways to get credit card payments, but however it's done I think it's playing with fire.
As a client I would never, ever give my credit card number to an agency or provider. They don't exactly hire a team of security experts to vet their websites, so I am sure many of them can be easily hacked. If you are taking to someone whose phone number you got on a website, it’s asking for trouble. I would’t do it in person either, even if it’s someone you know. They may seem be ok now, but can change later, and it’s not like you can just all the police and report it without consequences to yourself.
So IMHO clients, providers, and agencies should never ever even think of taking or using credit cards. There is no reason to throw this dirt on your grave.
