I'm not sure it is security theatre, these sweeps may well be very capable of finding hidden cameras. Then their failure to find anything demonstrates that the

I'm not sure it is security theatre, these sweeps may well be very capable of finding hidden cameras. Then their failure to find anything demonstrates that the danger has been severely overstated in several locations, that seems like valuable knowledge to me. Decreasing uncertainty is an important aspect of providing security. Of course, the scans could be incapable, either by neglect or incompetence, and then they do provide only false security.