As a foreigner in Japan, you get used to hearing about all the things you aren't supposed to do: drop someone's business cards in the soup, stick your chopsticks upright in the rice, use the black stripy envelope for wedding money, write snarky newspaper columns — the list gets pretty long.
Like everyone else, I generally try to keep my end up, though I nonetheless do occasionally find myself tramping around the tatami room in my outdoor shoes looking for whatever it is I have remembered I need immediately after tying up my laces.
One thing I am pretty consistent about not doing, however, is participating in political demonstrations. I have several reasons. First, I am lazy. Second, I am in Kyoto, whereas most of the interesting demonstrations seem to involve going to Okinawa or Tokyo (see previous sentence). Third, I am often not comfortable that I have adequate familiarity with all facets of the issue to take a side by demonstrating. Fourth — and most importantly — there is that 1978 Supreme Court case.