A young friend Cassy, who is planning to visit Japan this year, asked me about customs in Japan that she should know about so that she doesn't commit some big faux pas. I passed along a couple pieces of advice like facing the right way when you use a Japanese toilet (well, hopefully no one is going to watch you whichever way you face) and keeping the Japanese bath water pristine clean but I thought up another one so decided to post on it here.
Everyone knows that Japanese take their shoes off when they enter a home. Being shoeless keeps the house cleaner (remember people sit on the floors and eat on low tables) and probably keeps the tatami mats from wearing out too quickly. The entrance to a house has a high step right inside the front door and people will remove their shoes, step into the room, politely turn their shoes around so that the toes are pointing outwards (easier to slip into when leaving) and don slippers that are provided by the host. I have yet to see a home that doesn't provide slippers for their guests (except my own because I often forget to put out the slippers. My guests have to grab some from the shoe shelf themselves.)
In my California home I never saw slippers except for some old lady fluffy slippers that was only good for the trip from Grandma's bed to the bathroom down the hall. I don't think anyone I know in California would be caught dead walking around the house wearing slippers! Of course everyone is wearing shoes, but even so I don't think anyone would consider wearing slippers when guests were present or even having a pair of guest slippers available! Not so in Japan! Guest slippers can get to be quite pricey and are part of the room decoration. If you happen to ignore the slippers provided when you visit someone in Japan the hostess will come running after you and practically slip them on your feet for you.
Not only are there room slippers, there are also bathroom slippers. Cassy, this is where I'm warning you! When you go to the bathroom, you take off the slippers you are wearing, leave them in front of the bathroom door (lets everyone know the bathroom is occupied) and put on the pair of bathroom slippers that sit waiting. When you leave the bathroom, you take off the bathroom slippers and put your own waiting slippers back on. Hopefully, if you've really got your manners polished, you turn the bathroom slippers around (toes pointing in) so that the next person can easily use them. Almost 100% of the time I mess up around this point. I always just go barreling out of the bathroom wearing the bathroom slippers and step right back into the conversation with the hostess. She usually freezes at some point and goes running back to get the room slippers I left at her bathroom door and then returns the bathroom slippers to their spot, all the time apologizing for being such a bumbling hostess that she should have such unidentifiable slippers (as if I don't know that I'm the big oaf who has forgotten the custom!)
This bathroom slipper custom is also seen widely at schools and various institutions. Usually the bathroom slippers are rubber things that your toes can hardly fit into and they sometimes even have the men/women logo on them so that there will be no mistake about taking off with them. They are extremely ugly things so I think someone has solved the problem of stolen slippers at the rest stops along the highway and in the hospitals.
And for the people who have the philosophy of "be prepared for everything" little fold away slippers that will slip into your handbag are sold and are very handy for mothers who have to attend PTA meetings at school. I always forgot mine at home and some teacher would run after me with school slippers.