For the average person, low population density means more miles driven. That’s a good reason to go for a vehicle that gets more miles per gallon. To the point that land and parking is cheaper, you might expect vehicles that sprawl with longer bodies and an aero shape to provide a good mix of capacity and fuel efficiency. The Tonka Truck design you see a lot of in the US isn’t especially practical for most buyers. A strong hint that most trucks aren’t purchased for hauling is that they don’t have an 8-foot bed equipped. It seems like the truck’s purpose is more to be a signifier of group affiliation.