Selling ass is illegal in the USA though (even though it shouldn't be)
And I think this is also targeted at pornography? I'm not sure where USA is in the pornography rankings, but I'm fairly sure it's nowhere near the bottom (sorry).
But the point is, even if it were all illegal, that's probably a matter for the police, not for private interests to deny an essential service 'just in case', or because 'we don't want to do business with those people' , etc.