Thai kathoeys are not all prostitutes. They are the ones with visibility to foreigners but within Thai society they exist outside of the bars near the Khlong Toei district on Sukhumvit Road. The first one I got to know well told me he was saving up to get transition surgery. This was years ago. I considered him to just be a flaming gay exhibitionist. While he did prefer sex with men, he could have been "trans", I don't know. Trans was not yet a fad.

When you speak of degrees of comfort/discomfort with men and women in the wrong WC there is an obvious double standard, but the reason should be obvious. Perceived threat level.