Privately owned. I think this is the issue, they don't give a shit. Plus for most legacy dealerships they don't care about the EV market, or know that people with an EV currently aren't really going to start shopping for a gas car when they pull in to charge their EV...
I lived next to Mercedes of Morristown. They put in a charger right in the front by the entrance probably because they were forced to by corporate. ALWAYS had a for-sale car blocking it, and no special "EV Parking only" type lane painting or anything.
I have to wonder how often people drove there seeing it on their car's touchscreen as a viable charger and then getting annoyed.
The laws also need to be updated, some states don't allow charging per kW because then they're classified as a utility at that point. So it complicates charging as you're paying per minute or per hookup which doesn't relate necessarily to the amount of energy being pulled.
I'm willing to bet most of the benefit of using Tesla charging stations is the ease of payment aspect more than the accessibility. You pull up and charge and don't have to worry about card-swipes, weird charges, etc.
I can't imagine the frustration of having an electric car and finding stations not in service and then having to find another one.