So software on the charger is the big cost? Not the hardware or the electricity?
Off topic: how much would it cost to run a charger continuously?
The software subscription fee was an ongoing cost to whoever installed the equipment, now that fee has been replaced by a per-use fee that’s part of what drivers pay. It’s easier for businesses to justify installing chargers if they know that it’s a one-time purchase with no ongoing subscriptions, fees, or management hassles.
Off topic: how much would it cost to run a charger continuously?
Depends where you are and how much electricity costs there. Could also depend on time-of-day if electricity metering in that area has time-of-use rates. The biggest level 2 chargers put out 19kw, where I live it would cost about $60 per day to run one of those chargers at absolute maximum. Realistically speaking it would be hard to run one full-time though, since the average EV has ~80kw of battery and would be full after 4-ish hours.