I've been to a few clubs, malls, theaters, restaurants, lots of casinos, and used the ladies room in all of them with minor thoughts about me being there.
By far the scariest time was Halloween a year ago while dressed in a fashion similar to Elvira in fishnets. I need to use the restroom but knowing it was Halloween and as much attention my costume was receiving I was pretty sure everyone knew I was really a male. So I just Man'd up and went to the men's room and stood at the urinals beside all the other guys.
It really turned out funny as the first guy who saw me said I think your in the wrong room. In my male voice I told him I thought the women in the ladies room would have told me the same thing.