Sometimes, foreigners come to the cafe where I working. I realized that people coming to Japan for sight seeing is not return used trays and cups when they left the shop. In our shop, customer have to return trays to a counter when they left. Don't foreigners have culture any like that ? But I guess in Mc Donald's in US they have to do like that. I wonder why they didn't as that. Do they think that Japan is different with other counties or cafe in US is different from us ? Anyway after I realized that I became to say them so.