It's because the standard way we develop neighborhoods does not lend itself to people being able to <i>leave their homes</i>. My parents just bought a condo in a newer development in a rapidly growing metro, and while they can walk around their complex, there's no sidewalks to anywhere else, and even if there were, the city zoning laws means there's no corner cafe, bakery, or small-scale store like there really ought to be. It's so stupid and such an easy thing to fix: just require that each adjacent complex have a right of way and sidewalks and zone for cottage businesses every few blocks. Makes everything more pleasant, and people have something to do when they leave their house without having to get into the car.<p>EDIT:
This [1] is the kind of neighborhood i'm talking about. Growing rapidly, cheap housing -- great, but they're setting themselves up for real heartbreak because the complexes don't connect. To walk to the park that's not even a mile away requires walking on a huge, busy road. All they need to have to make it not feel dangerous is a dirt path and a required gate between complexes. That's it. [2]<p>I'm honestly not sure why we think this kind of development is even normal. Roads really ought to connect. It also makes the traffic so much worse. I live two miles from downtown Portland and my street outside my house gets significantly less traffic than my parents.<p>I fully expect to move my parents somewhere near us as they age. It's just not possible for them to leave the house when they get older without having to drive, whereas older people in my grid-based, sidewalk neighborhood can walk for miles and achieve their entire life.<p>[1] <a href="https://www.google.com/maps/place/Clark+County+Fairgrounds/@45.7484249,-122.6642113,3200m/data=!3m1!1e3!4m6!3m5!1s0x5495b281e73740e5:0xb3a2f97437960dd5!8m2!3d45.7465972!4d-122.6645667!16s%2Fg%2F1td04rzp?entry=ttu" rel="nofollow">https://www.google.com/maps/place/Clark+County+Fairgrounds/@...</a><p>[2] Meanwhile, our park is technically farther away (about a mile) and we walk there almost everyday and know all the neighbors down the street. We just went to a party at one of the neighbor's homes and the only relation we have is that we wave at each other as their kids play in the yard and mine ride their bikes to the park. I want to leave the house half the time because I have friends outside. That's all you need.