I had a new colleague shadowing me today to find out how I run my project.
I asked her if she wore shoes in her apartment or removed them at the door. She said she always removed them and thought wearing shoes indoors was disgusting. She said that in a previous job, she had visited homes and had worn slip-on shoes so as to remove them, often surprising the people she visited by doing this.
This colleague was from Birmingham. I told her I believed that removing shoes was more common here in Hertfordshire and the south-east.