It's a bit more complicated than that. Yes, you need to run the sewer pipes farther, for instance, but the land occupied by utilities is much cheaper, labor is

It's a bit more complicated than that. Yes, you need to run the sewer pipes farther, for instance, but the land occupied by utilities is much cheaper, labor is cheaper, and it isn't a major catastrophe if you have to close a suburban street while you're burying the sewer pipe.