REF the recent FL massage sting
I've copied (and reposted it here) this question and answer. I found it on the Huntsville, AL. Massage board. I'm not vouching for its correctness, just saying.
Still not sure how they identified these guys. Were they caught in a sting, or was the place keeping records?
Florida has what is called "sneak and peek" warrants which allow infiltration and covert placement of video cameras. Reading what available press found, it seems there was an evacuation called in the plaza where the spa is located over a "suspicious package" (placed there by LEO). While all businesses were cleared, under the guise of a search of all establishments to clear the area the cameras were placed. I should there has been a history of less obvious methods of placing cameras as well, including after-hours infiltration.
Once cameras were in place, it was a simple matter of pulling people over after seeing them exit the establishment under whatever pretense needed. Their identities could then be established and recorded for future cross-reference against video evidence.