This is a good point, but the obvious solution is to rent parking spaces at something like a market-clearing price.
If a food truck can outbid people who want to park, then the city's economy needs food trucks more than parking spots.
If a food truck can outbid people who want to park, then the city's economy needs food trucks more than parking spots.
It would be difficult to justify a demand system since day passes for parking meters are sold for things like moving trucks well ahead of time (how do you price something on a random Tuesday two weeks ahead of time?). However, the day parking passes are quite expensive (~$200 for 4 spots all day), so I'm not sure that even at peak demand, the city would make more than that in meter fees.
I don't disagree with that in a location like NY where parking is in very limited supply.