I suggest it because in city locations where people are using superchargers for all their travel (Tesla has installed stations in large cities like Hong Kong, London, Shanghai, etc where they are intended for this use), the prepaid model is unsustainable and can't scale (it only works if ~10% of total travel is on superchargers). Given the network is primarily for long distance travel, it doesn't make sense for Tesla to subsidize this use forever.
It scales just fine. Stop thinking locally. Think globally. Whether a Supercharger is set up in Yazoo City MS and sees a visit two-or-three times a month... Or is set up two blocks from Times Square in New York NY and handles dozens of Customers per hour... They are still on the SAME network. You service your Customers where they are... You service your Customers where they are going... You service your Customers on the route they choose to take between them. ALL of your Customers. The resources spent to service Customers at any one location have been gleaned from Customers everywhere. It is not necessary for one, singular, specific Supercharger location to be treated as if it is a lone entity that must validate and sustain itself.
If one presumes the majority of Supercharger stops will be 30 minutes... And that the majority of gasoline station stops are over in 5 minutes... Then Supercharger saturation needs to be six times greater than the installed ratio of gas stations to ICE.
There are 250,000,000+ ICE vehicles in the US. There are only 25,000 SHELL service stations in the nation. So, SHELL is confident that a 10,000:1 ratio of vehicles to their own facilities is sufficient to handle incoming traffic.
Using that principle, a ratio of 1,667 Supercharger enabled vehicles to every Supercharger location would be appropriate to match SHELL. There are currently around 68,000 Supercharger enabled vehicles in the US. Those are serviced by 256 Supercharger locations. That is a 265:1 ratio.
Thus, Tesla Motors is already well ahead of the demand curve. Yet they are continually expanding the Supercharger network anyway. When Superchargers were first introduced, it was theorized that 200 locations could potentially cover the contiguous 48 in the US. Hardly 3-1/2 years later there are over 250 locations, 4 under construction, 16 under permit, and a whole bunch more yet to come by the end of this year. Both Distance and Density will be served.
I don't think the toll road analogy is the right fit. Rather, such paid superchargers will be more like your neighborhood corner gas station (or charging station). Rather than part of the "supercharger" network, it'll be a separate network like the rest of the paid charging networks (like EVgo or Chargepoint). The only difference is that the charging speeds are much faster than existing networks (it doesn't even have to be run by Tesla, it can even be franchised out). And my suggestion is only as a stopgap while non-Tesla charging solutions catch up. If local non-Tesla 150kW charging stations become common, such a network would be unnecessary.
If you believe that is a viable means of doing things, by all means invest in your own paid charging network for urban use. You will get your wish... Charging locations that are clear of the riff-raff and ne'er-do-wells... A place where a paying customer doesn't have to worry about being harassed by the masses, taking up space, and getting in the way. The notion has worked so well for gas stations, after all -- there's never any waiting or lines there. Of course, there wasn't likely to be someone diagonal across from SHELL station that was pumping FREE gasoline... If I were not sick as a dog, and up past my bedtime, I'd create a nice logo for
'StopCrazy PP Charging' and you could get right to work! Of course, the Tesla Supercharger diagonal across from your chosen locale may act as a bit of a buzzkill on sales... Be sure to have your lawyers draft a proper
'non compete' clause when you ask for that charging franchise. Rots-O-Ruck, and stuff.