Fishman - take a moment and think of it from this perspective: in the 60s, many people argued that blacks should not be allowed to live in redlined neighborhoods, because if there were black residents and you saw a black person, it would be hard to know if he/she was a resident or a criminal (cause, you know, most black people are criminals, right?) who came to burgle the houses. Therefore, in the name of protecting the safety of the current residents (white people), it was justifiable to keep out black residents, just to be sure.
This is the *exact* same argument that you are making. “If we allow people who look different to be in the bathroom (i.e. neighborhood), then criminals who look like them could try to blend in.”
Crap argument then, and (literal) crap argument now.