It's as simple as you apparently ignoring my point or else you are using another strawman. Again, if there is a problem why not just patrol the bathrooms? Why the need to engage in questionable police tactics?
I don't pretend to know the most effective way for an Airport Police department to do its job. Neither do you.
How do you know they weren't patrolling? In addition to this stake out? I've got no problem with a stake out, if there have been numerous legitimate complaints to the cops, about lewd activity in an airport bathroom. I consider that part of their freakin' job.