It's a good thought. And contractors are virtually all commuters. There's a lot more driving than in most professions I can think of. In cities with awful traffic, going and buying more screws or plywood might be a day-ending problem. you might wait extra hours for deliveries, too.

All in all, frictional losses/expenses building in a city are probably very high in aggregate. The few builders I know sure seems to spend a long time waiting. Meanwhile, when I lived in CT, a round trip to the hardware store usually took about 30 minutes max.

I wonder if/when those frictional losses/problems building in dense cities actually balance out with the gains in reduced commutes and greater efficiency of urban life once those buildings are occupied.