I don't get them nor do I want to. If they happen to be logical and sensible, sure, I got no issues with them. But from Jazz circles to the more administrative and official stuff, Japan's culture is imbued with customs that range from menial and tedious to downright illogical and counter-productive. And sometimes they are just made up on the fly. Yet the real kicker is that these are highly expected to be followed by all. Expectations ruin. Ever since I started living back in Asia, 'The Age of Innocence' has personally become the most relevant and relatable movie of all time. It's another one of Scorsese's film adaptations from a novel- this one, penned by Edith Wharton. Go watch it. If you feel a deep agonizing pain and sorrow in the general area of the heart by the movie's ending(an easy feat, thanks to Scorsese's masterful direction), perhaps there's still some hope for you.
[Addendum] To be clear, "customs" are not the same as the law. Sometimes they can be. But they are still two separate things. I abide by the laws of the land. In fact, I have paid a heap of yens to do so as a foreign entrepreneur over the last few years. So, when folks react to articles such as this with the typical question, "then why are you in Japan?", I don't like to justify such the logic of a teenage princess by trying to answer it straight but rather, pose another question of the same logic; "when life gives you sickness or hardship, why do you bother living on?". We don't choose to be born in this world. All we can do is to make it worthwhile.