You're absolutely right. We should be encouraging density to save energy and be ecologically friendly. What's most wonderful is that we don't even need any new technologies to do it!

It may be possible that this is something of a politically difficult problem in many areas, though. Until San Francisco actually allows itself to become a real city, we may be stuck looking at workarounds. It's very, very, very far from ideal. Exactly as you say. But it may be the best we can do for now.