just so you know prostitution isnt illegal everywhere, so here's something to think

If an US citizen pays to prostitute at overseas can US sue the prostitute for offering the service to united states citizen where it isnt illegal?(assuming states finds out about it somehow)

Because this is basically the same, a serviceprovider offers a service thats legal in the country the company and hosting is based on for customers of said country. When someone not from the said country finds out about the service and starts to use it the company is doing something illegal? Internet is global and it is nearly impossible to make a service that ISNT ILLEGAL SOMEWHERE (see china & citizenrights/laws)