(3) Culture of Slippers
Japanese are sometimes amused when foreigners make cultural faux pas, but when it comes to mistakes about changing shoes, some people get genuinely upset. The need to change shoes is not specifically a religious practice and performed in other countries. However in Japan, the Shinto belief of frowning upon impurities is deeply rooted in the psyche of the people, so importance of changing shoes is more than hygiene. Outdoors shoes are “impure” and should be taken off before entering the sanctity of a home. And guests are usually asked to wear slippers. There is a separate pair of slippers for toilets usually. Toilets are unclean places and toilet footwear should not contaminate living areas, so you need to change slippers before and after.
1) Toilet slippers and hall slippers are separate.
2) Do not wear slippers in tatami (floor mats for Japanese-style rooms) mat rooms.
3) Indoor running shoes are required at sports facilities.