I'm not an urbanist, but my feeling is that the size of the lots and the winding paths of suburbs make the paths from any house to any shop a lot longer overall

I'm not an urbanist, but my feeling is that the size of the lots and the winding paths of suburbs make the paths from any house to any shop a lot longer overall, so you end up with the need to drive to a store, which leads to parking lots and being in a main road. In a tight grid (like where I grew in Chile), a small store can survive off the foot traffic of a few square kilometer of houses, because they're more connected and just more fit in the space.