Echoreply has pretty much summed it up. I suppose the mandate for electric utilities disallowed others to resell kWh because they did not want some subdivision developer or whatever to set up their own electrical grid - quality unknown - and resell the power at a premium to their local homeowners, or other such schemes. Apparently the rules changed recently to allow resale by the kWh for car chargers.
My home charger (Tesla Wall Charger) is on a 50A circuit breaker, but code says only countinuously run at 80% of top rating, so 40A. With 40A/240V I get about 58km/hr added to the battery. Recommendation is as much as possible to keep the battery between 20% and 80% or 90%. So I have it set to automatically start charging at 1AM if plugged in - when I’m no longer using the dryer, hot water, oven, etc., AC demand is less, since the house only has 100A service. At 58k/hr (34mi/hr) I’ll be full by morning.
For similar (L2) charging, there are assorted locations that provide it either for a fee or free - I stayed at a few hotels with a complimentary L2 charger or two, but it’s a toss-up whether they’re already taken nowadays.
Plugshare.com lists the plug-ins available in North America. Supercharge.info is a list of Tesla chargers.
For L3 (fast) charging, I don’t think I’ve every charged more than half an hour. I’ve run across chargers that will add - when the battery is around 20% - up to 1000mi/hr, but it gradually slows down to about 200mi/hr or less as you approach 90%. I have had a few instances, especially in the Toronto area, where the chargers are full during a busy time and I’ve waited 10 or 15 minutes for a spot. I’ve rented Teslas from Hertz a few times and had minimal hassles. The car’s computer will tell you where the nearest Tesla fast chargers are, and even how much charge will be left in the battery when you get there.
Some juridictions now make it a ticketable offense to block an EV charger with a non-EV car (not unlike tickets for using handicapped when not qualified).
The portable charger that used to come with a Tesla (now an optional accessory) also has an option to charge from a stadrd 110V/15A circuit (L1), but that will only add about 3mi/5km an hour, so it’s a “limp home” last resort to get to a good charger.
Home charging works out to about 1/10 the equivalent of gasoline (YMMV depending on kWh charges) whereas fast charging seems to work out to 1/2 the price. The real savings is, of course, in typically charging at home unless you’re on a road trip. You start each day with a “full tank” which is a different mentality from a gas car.
I’ve never worried about non-Tesla chargers. I’ve tried ny ChaDemo adapter once. As an older standard, it charges to a max of 50A (350V?) whereas CCS1 is alleged to be able to provide 350A and most Tesla fast chargers are 150A or 250A. CBC Marketplace program did a bit on driving an EV Toronto to Ottawa in winter (yes, your mileage is worse in winter) and how it was difficult to find chargers, they often did not work or did not connect. (And then they took the Telsa to a Tesla charger and “no problem”.) Although why they thought it was a good idea to try to go 420km without charging I don’t know…
Tesla, BTW, you have yor credit card on file with them, and it gets charged when you charge - the car identifies itself to the charger automatically.
Things are just getting started. As OP mentions, there are still plenty of places, especially remote, generally out of range. So many chargers have been added and not maintained. The charger networks are getting more common, and eventually they will likely be as common as gas stations are now. However, unlike gas stations, they can be everywhere with minial support; no big tanks, no attendant, single charger or large bank.
The major problems are obvious - if an apartment building wants to put in a charger curcuit for everyone -first the wiring has to be able to handle that; no guarnatee that all the occupants will respect “please charge at night”. Apartment garages (or worse, outdoor parking) are not wired for that level of power. it becomes expensive to accomodate and not something that can be done piecemmeal beyond 1 charger. There are areas of the city - townhouses, no garages, no parking - where there’s nowhere to put a charger. My house could accomodate one charger, but not two. For two cars, i would have to alternate or run out and move the plug in the middle of the night. (Or, with two Tesla wall chargers, apparently they can be connected so they cooperate and share the total load. )
Like most tech, the future looks better than today.