When you study psychology, you are interested in what is "normal" and what is "abnormal". This is not to be confused with "average". "Average" is defined by statistics and can be quantified. "Normal", on the other hand, cannot be quantified and is relatively subjective.
Most people believe that they are good judges of what "normal" people behave like. They know this mainly because they define "normal" from their own experiences and upbringing. Part of the reason there are frequent problems when new members join a family through marriage is that each family defines "normal" using their own experiences as a template for what is reasonable and expected behavior and frequently fail to realize that every family is a culture unto itself, even if both families reside in the same small town and have the same ethnic history.
Considering how ubiquitous in-law problems are among people in the same culture because of different concepts of what is normal and expected, you can imagine how much more complicated the situation can be when people compare lifestyles and psychology between cultures that are separated by oceans rather than by miles. Recently, I had a discussion with a student which pointed out rather dramatically how what a Japanese person might consider "normal" behavior differs from what an American considers to be "normal".
My student and I were discussing the way in which Japanese men regard Japanese women (in general). I told her that I felt some Japanese men frequently objectified women and saw them as inferior to men in status. I told her I also felt that many Japanese men treated women as less important than men and didn't respect them. To support this assertion, I told her that the way in which Japanese men frequently grope women on the trains is some evidence of that. I believe the reason Japanese men do this is that they aren't considering the feelings of the women they do this to and are simply using them as objects to satisfy their own urges.
My student disagreed with me because she sees the behavior of men in this regard as "normal" and a part of the nature of all men. She told me that, when she was younger (she's now 44), she was groped every single day on the train when traveling back and forth to university and at one point was fondled simultaneously by three men. She also told me that, when she was 7, she was touched inappropriately by a man in a situation which was clearly not an accident but she didn't understand what was happening. After she was touched, she looked up at the man who did it and he smiled at her. Since she didn't know what was going on, she smiled back. When she went home and told her parents, they bought her a small alarm and told her to use it if it ever happened again. I must say, this incident really made me cringe as she innocently encouraged that creep because she was too naive to know what he was up to.
At the end of telling me about these experiences, she said that women endure this because it's just something that happens everywhere. I asked her to clarify what she meant by "everywhere" and she said "all over the world". In my student's view of "normal", men grope and fondle women regularly and the women put up with it. She was surprised to learn that this level of perversion does not occur in the United States. While I'm sure it does happen everywhere, the scale is nowhere near what it is in Japan and women do not passively put up with it in America.
My student did mention that women now are far more likely to protest compared to what it was like in the past. About a decade ago, the metropolitan government and public transportation agencies started putting up posters telling men not to molest women on the trains. This happens on the trains mainly because it's crowded and men can pretend it's an accident if they are confronted about it. Some of the train lines also have designated special cars for women only during the peak travel hours when groping is most common.
Japan isn't the only country where there are problems which are considered relatively "normal" because they occur so frequently. One thing I'd like to be clear about is that "normal" does not necessarily translate into socially-condoned, legal or acceptable. In the U.S., we consider petty theft a relatively normal experience, particularly mugging and pick-pocketing in large cities. In Japan, such theft would be considered an unusual experience.
One of the most difficult things to do when you learn about a foreign culture is to resist viewing its "normal" negative aspects as more omnipresent or despicable than the common negative experiences of your own culture. Our natural reaction is almost always going to be the most ethnocentric one when we encounter something which is outside of what we consider "normal".