This is a really interesting tangent to go off on. I wonder if the reason for this is that Japan and Korea never really had a frontier the way the US did. I think the idea of a wide open wilderness, yours if you can tame it, contributes to a desire and expectation of a giant living space, all to yourself.

I don't know about Korea, but in Japan, most of society grew up around castle towns, and with the exception of post-war suburban development, those towns are still the same towns they have today, so population is distributed roughly the same way as in medieval times.