FWIW in non-rural Canada we sometimes have gravel roads in towns twice that 10k size and in the metro area of a multi million inhabitant city (of which there are not all that many in Canada :)).

Not saying it's common. I don't have to drive over one of those but I have had to when there was construction on our regular route. It's right off the main road leading into town from the highway.

Here’s a house in San Francisco that’s on a dirt road: https://maps.app.goo.gl/UeLKZmXAcHUhTn848?g_st=com.google.ma...