wikipedia claims the term "gaijin" is mostly neutral and simply means "foreigner" but my buddy's japanese wife says it carries the connotation of "barbarian"^I suspect you would catch an earful at the least. If aforeignergaijin did it a little old lady would emerge out of nowhere with a tiny broom and clean it up. A Japanese would be beaten with that broom by the lady.
my first surfboard ended up on Okinawa
would love to go spend a few months searching for it