As I said earlier, in Sweden its the norm, but I must admit, I was a District Nurse, and especially in the Winter, it was a nuisance on and off the shoes all day visiting patients, in some places we had those blue plastic over shoe things, which were good if the places we were visiting were a bit "dodgy" cat/dog hairs and other things!
Then as another gran said, tripping over a mound of shoes when coming through the front door is a hazard to say the least. One point to remember, if having those very "attractive" blue plastic creations, dont forget to take them off when leaving!