I think people do not realize how hard it is to make the creature comforts you are all so used to. No one thinks of the massive bio plants, wastewater plants, construction companies etc that create the comfortable world we live in. On the surface sure, you live in a nice compact apartment with 1000 other people so the land is densely populated, but you still had to build on that land, all the wastewater needs to be treated, and you're going to have people who don't want to live squished together. Hence what we have today. Urban sprawl may suck but when you get your own house you don't really care anymore.

Also you can't have a sustainable society when we keep increasing population, and everyone's idea of sustainable is different. One person may be satisfied to have food and read books all day. The other one may want a Woodshop so they can build. The other one may want a large garage so they can work on old cars...see where im going? Sure if everyone was content to sit on a couch all day, our idea of a simple sustainable life may work. But some of us are doers.