A couple years ago, I was looking at how economically feasible it would be to have a parking area just for people to get some shut-eye securely. However, there were just a ton of costs that made it not workable unless there was another income source from the property like a 24 hour store.
There are a lot of regulations, and asking $10 to park can open up a lot of can of worms, such as ADA compliance, having to have working restrooms on premises that can handle the people parking, etc.
The best way to go about having dry camping/parking would be to have three things on site: A 24 hour shop or gas station, a full service CG, then an empty parking lot. That way, the revenue from the gas station and the CG will pay for the capital needed to keep a parking lot going.
It is a good idea, but it is something very difficult to do because it takes a lot of capital outlay for the real estate. In some places, $40 a CG asks can barely cover the real estate taxes, sales tax, bed taxes, liability insurance, Wi-Fi coverage, electrical/plumbing/sewage, road upkeep, grounds upkeep, security and rules enforcement, and the cost of the employees to work this.