For example, they can cap the footprint of parking lot space, leading to stores building parking garages or taking their own steps to minimize freeloaders through metering. That's just an off the top of my head example.
Never say the govt "can't do something". The have power of eminent domain, as an example of how far they are able to go when the actual will is there to have something they want. Check out the history of the new Fenway Park for things they can do.
Why couldn't our city councils tax each parking space? Landlords would pass that on as a parking fee.
Car owners kind of already pay for infrastructure for their vehicles through excise tax, gas tax, and tolls (not really, but at least its something). Why not charge for parking too?
so many other things are imposed on private property, so I don't see why suddenly paid parking is the "limit'