Isolated spaced out households need more roads, more travel for goods, more pipes, more stormwater treatment, more services (as each needs a larger buffer to sm

Isolated spaced out households need more roads, more travel for goods, more pipes, more stormwater treatment, more services (as each needs a larger buffer to smooth spikes in demand), use an order of magnitude more energy to heat/cool, take more materials to build, require more vehicles. You may only need to build up a little to fix most of it, but sprawl uses much much more of everything than building up.