Shoes ~ and new (-to-me) rules

I know to take my shoes off when I enter a home or church building or some restaurants.

Several years ago, when waiting to enter a dressing room, I noticed that the shoes of the customer in the dressing room were outside the dressing room. And so I learned that I need to take my shoes off before entering a dressing room.

Today at the doctor's office I noticed two more places where one is probably expected to take one's shoes off, two places where I have never done so. Oops!

Slippers are conveniently located next to the curtained-off changing area in the x-ray room, for one to wear when stepping up onto the stand-up x-ray machine.

Then in the lab I noticed a patient take her shoes off to step up onto the scale.

I wonder what other places I should have been taking my shoes off all these years!