I don't remember if I've mentioned the following things, but Japanese people seem rude to me with the following things.

1) I'm crossing the street between two lights. Cars are stopping at red lights in both directions. I think many cars in America would waive you on. Here the cars will just keep going until they are completely stopped at the light, even though there is no where for them to go.

2) They want to get me something to drink at the elementary schools. However, they don't ask what I would like to drink. So they bring me coffee or tea, very often not something I want to drink. It seems strange to me that they don't ask what I would like, or if I would like a drink at all. I think it is just their way though.

3) I am about to walk through a door behind someone and the door is slams in my face. They don't hold doors for anyone. Quite often they don't even seem aware that someone else is coming through the door. I held the door for someone the other day and he got really flustered. He kept saying thank you profusely.

I don't think they're trying to be rude, but it is just my perception of what is polite or not. They undoubtably think some things I do are rude too. But of course I'm not trying to be rude either.