That's what happens when your brain becomes a tragedy of the commons.

Some friends and I dreamed up the table of contents of the "Geocities Web Design Handbook," but I think it would apply to Japanese commercial web sites and streets as well.

  Part I.  Basics
   Chapter 1.  Rational thought:  your enemy.
   Chapter 2.  Serenity, comprehension, and other bad design smells.
  Part II.  Basic applications
   Chapter 3.  Maximizing information density using randomly sourced content.
   Chapter 4.  Total coverage:  cross-browser design techniques to banish white space.
  Part III.  Advanced techniques
   Chapter 5.  The BLINK tag:  sissy crutch.
   Chapter 6.  DOSing the visual cortex:  advanced techniques to overwhelm and disorient.

That said, a huge amount of the buildings in Japan are somehow different from others (different shape, color splashes, wall art), and there's a lot of random green spaces (usually with a shrine of some sort) in even the densest / most businessey areas. There are, of course, the standard looks like your map example, and cheap apartment housing that's the same everywhere in the world, but I've yet to see that amount of diversity anywhere else as the rule, rather than the exception.

And it's not all megabuildings, either. I'd wager that there's some pretty green space within easy walking distance.

I'm just not sure how to reconcile in my head this type of urban layout with the Japanese aesthetic.

Actually, that's how I react to most American city planning these days, now that I've learned what a proper city can be.

My theory is that Japanese (and Chinese) readers process a web site differently from readers of word-based languages, such as English. Japanese readers do a lot more 'scanning' than we do.

It would be interesting to see a usability study of one of those Japanese sites that records how the user actually processes the page.

Here's one

http://www.danciprari.com/images/worldtrip/japan/ja-tok-stre...

Of course this is Shinjuku which is normally kind of loud. But you can find this type of street scene all over Japan.

Like this

http://img5.travelblog.org/Photos/40770/225034/t/1787494-Jus...