Even out there, it's a pretty rare use case. If you're somewhere so remote that you can't get there with any kind of land vehicle, then... what are you even doing there, that you need a semi-permanent solid structure?

Happens all the time here in Alaska. There are many medium-sized towns and villages that are accessible only by air or water.

Heck, not even the state capital (population 31,000) is on the road system.

The page itself has some good examples - really remote on montain tops e.g.