Not only that but you pay sps for their services which can include sex...... Sps consent to safe fun and if you remove a condom , she can charge you with sexual assault ; if you refuse to pay she can charge you for theft , or again sexual assault because you would have taken advantage of her.
Nearly impossible to prove in either case. Just because unprotected sex took place, doesn't mean it wasn't consented to. If there's no evidence of a struggle, an SP is unlikely to prove to the court that it wasn't consensual.
As for theft via not paying, that's also very difficult to prove as SPs do not sell tangible goods that could be found in the client's possession. The onus to prove theft is on the SP, and I don't see how she could do it.
Of course, both these scenarios would rightly get the client blacklisted. It's unfortunate that we don't live in an environment where more legal action could be available to SPs.

