When I was growing up, I was a rabid KISS fan. Some of my more attentive readers with good memories may recall this fact from some of my previous ramblings. One of the reasons I loved being a KISS fan and found it so hard to stop being one long past the point of actually liking the band was that a huge part of my identity was wrapped up in my association with the group. Like many young people who went through an identity crisis, I found a bunch of people who seemed to be "like me" and built a lot of who I perceived myself to be around that. This was something I needed to do because society at large wasn't giving me any clues as to what it was to be "American". In fact, if society told me anything, it was that Americans had no real identity. We were part of a crazy stew of diversity.
The Japanese lack this mixture, and as a result, they know who they are. They don't have to reach as far afield to know what their identity is and as a result are a lot less sensitive about trivial things. What is more, and I think this is one of those hidden aspects of life in Japan for some foreigners which they are gratified by, but don't even realize is valuable to them, they give us a solid identity as well. We are "gaijin". We know who and what we are because the Japanese tell us so. For people who have just graduated from university ("student") or have faced a life transition ("mother", which is lost as part of empty nest syndrome) and who lose an identity, the power of being given a definition of self is not to be underestimated and even a negative identity is better than the gaping emptiness of not knowing who you are.
While I was never happy to have it crudely and rudely pointed out to me, I nonetheless miss the fact that I had a solid identity in Japan and could relate to the Japanese people in a particular way because they who knew they were.