Hard to find someone to agree with on this situation, since the relevance to each argument is situational. There are going to uptight people who are rigid about their customs and there will be more open and understanding people.
One big issue that I see conflicting here is the mixture of high and low context societies. Two great examples of a high and low context culture is, of course, Japan and the US. Japan has cultural bits up the wazoo. America has hardly any beyond basics or it has small sub-cultures that have to accepting to the other cultures around them. Therefore, it sort of makes sense that the enforcement of culture is a one-way issue.
However, I found that while I was in Japan that people there were pretty tolerant of my ignorance of certain things. There were many times that I spoke my mind (honestly) and while I did realize this wasn't something I should do too strongly in Japan, I was actually complemented for doing so! I never got used to the bowing thing, I usually got away with just a nod (most of them usually only do a sort of nod anyways). And I am sure there were things I got away with that I didn't even realize. But I did try to fit in for the most part (I was there for the culture after all). I am sure they had just a hard time grasping what it meant to be someone from a low context culture, where we communicate everything straight-forward and set up an environment where people can't make as many mistakes (whereas Japanese have an environment where you are expected to do certain things).
Another example is when I had a Japanese teacher who taught math at my university (judging from her thick accent, came from Japan herself), she would not give out her first name in her introduction as any other professor would do. She insisted that her first name was a private thing and that she's only comfortable with people close to her knowing (although it was easy to just look it up
). We thought she was weird for this (although she was strange in other ways too), but we did not tell her all that "when in Rome" crap.
Tolerance comes from knowing how your culture is compared to other's. If people can't help it or just don't feel right, conflicting with a culture, either tolerate it or come to a compromise. There's so much gray to the issue that it's hard to make it black and white.