In many Japanese offices, staff and visitors remove their outdoor shoes and change into slippers. This seems absolutely absurd to British people. However, I think that it is quite sensible. In my experience, nearly all offices have really dirty carpets.
However, I realise this would not be practical in the office where I work part-time. People continually come and go between the office and the warehouse. It would not be a good idea to wear slippers in the warehouse.