Cambridge MA was rezoned in the mid-20th century to suburban standards, in a city where land in a mid-range neighborhood now costs $350-$400 per square foot. Besides putting in floor area ratio requirements that required most of the existing housing to be grandfathered, they added a requirement of one parking spot per unit.

If it's a traditional 1-car driveway that's about $70K worth of land, although in the end it's zero-sum because it takes away an on-street spot. Parking garages for larger developments probably cost as much or more per parking space - they use less land, but they're expensive to build.

It's insane, and they're trying to fix it, and approving special permits left and right to omit the spots.