I worked in Sweden for several years, where it was standard practice to remove outdoor shoes as you came in, and add them to the "shoe shrine" adjacent to the door. I think that this was partly because so many homes have polished wooden floors, which could be scratched by rough soles, particularly during the long Winter months when so much rock salt is about. As regard U.K., I usually continue to wear my outdoor shoes around our carpeted house, and wouldn't dream of asking a visitor to remove theirs. If they choose to take them off without being asked, that's OK with me.