I have only had one experience that was troubling.
I went to a spa many years ago, and after coming back from the shower room I thought my pants that had my wallet looked like they had been moved, but before leaving I checked and nothing was missing.
A couple of days later I had some credit card charges on line, and I cancelled my card, which was still in my wallet.
Coincidence? Maybe, but since that time I always take my wallet with me to the shower room, and don't leave my wallet alone in a room where I am not.
If the girl looks at me as if to ask why am I doing this, which is rare, I explain that I had a bad experience a long time ago and I don't want there to be any misunderstandings.