Well, see, the secret is you probably don't really need that truck bed in the first place, so if I was to guess, I'd say that's why there's a bit of resistance to that idea. The working hypothesis here is that if you bought a sensible car that makes sense as a car... and a separate van to work, then you'd never buy a van. Which is what most people do here, honestly. You don't so much buy a van as you know a guy who does own a van and will let you use it for the thirty minutes that you actually need it once or twice a year in exchange for a beer later.
Which is probably how you end up with fewer cars per capita than the US and still have work vehicles separate from whatever you use to take the kids to school or go get groceries.
Also, you send the kids to school in a bus and walk to the shop. That also helps, I bet.