In this article concerning the raise in rates at the Des Moines airport, they comment that "the airport needs the money." I don’t have a problem with that.
See the airport isn’t a public entity the way a city is. Taxes are raised and fees are paid to support a city, however the airport is paid for by its specific users. People who go to the airport pay fees either through their tickets or with their parking, for the right to use the facilities.
Taking money from parking and using it to provide other services at the airport makes sense, since the folks who parked with use those services. It doesn’t make sense in a city.
In a city the people who park on the street are doing so to be able to reach their homes, go to a park, attend a meeting, eat at a restaurant, or just about any one of many other activities people do in communities. The parking is a resource provided by the city for that purpose. The money generated off that resource should protect the parking, and support the direct area around it — sidewalks, streets, lights, and the like. Not become a cash generator for the general fund of the city.