Worth reading Tyler Cowan's take on this:

http://www.marginalrevolution.com/marginalrevolution/2010/08...

* It's going to be hard to properly price all that parking, and if you do it wrong, you wind up shifting the problem around (from K-Mart's parking lot to neighborhood streets).

* The same externality might be addressed better with a lump-sum tax (Tyler Cowan is not exactly a tax fanatic, by the way).

* If urban congestion and land use are the problems, you can address them with satellite lots on the outskirts and mass transit.

* The effect on "poor people" is probably salubrious: many of them don't own cars to begin with, and without parking lots vying for land, land prices will go down).