Maybe zoning. In arglinton, Texas, often called one of the least walkable cities on Earth, there's a requirement that each building has a parking lot proportio

Maybe zoning. In arglinton, Texas, often called one of the least walkable cities on Earth, there's a requirement that each building has a parking lot proportional to it's occupancy. So if you build a 200 person building, you need a parking lot to handle 200 people. I can't remember the exact ratio, I doubt it was 1:1 like that. So the parking lots are there by force, not convenience or cost.