I was doing my crazy 11 PM- 4 AM shift at the hospital. In the staff room I asked a nurse if he wore shoes in his house. He said that he had done, but he had a new carpet, so he and his wife were now starting to take their shoes off. They also had a hardwood floor in the hallway and were a bit concerned about the effect on it of high heels (good thinking for them, some daft people think hardwood floors will take any amount of punishment).
This nurse was very conscious of the filth that one can pick up on shoes. We both agreed that on a night shift, we were likely to be walking in some really nasty stuff!