Right, and this is a big part of the post-war economics. After WWII a huge number of people were looking to buy homes in an unusually short span of time, and they pretty much all wanted a "typical American home" with lawn and fence. On top of this, there was a large workforce available that basically kickstarted the American homebuilding industry as we know it today, and made buying a brand-new home a very affordable and attractive option.

And what do you get when you have a huge number of people looking to buy brand-new houses? Urban sprawl, there's not really any way to avoid it.