That's how they do it in Ventura County, CA. Not only massage parlors, but "physical therapy clinics". They have one licensed physical therapist who drifts into the office once a month or something to make it look legit, but the rest of the time it's just "therapy technicians". They just did a big bust in Simi Valley (our next nearest town) a month ago:
Simi enacts moratorium on massage permits Ventura County Star
They stopped issuing permits to operate massage parlors and therapy businesses. The City of Dallas also did a sweep like that in the last couple years. As long as they keep prostitution illegal, it will find it's way into commerce somehow. Who knows: Maybe there will suddenly be a big boom of mens' grooming business.... Get your back waxed and your needs relieved at the same time (for an add'l fee, of course

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Charles