The first gen volt generator can actually help push the car as well. Most of the time it's just putting power into the electric motor but if you really push it with an empty battery the engine will engage and help push the car directly.
I have a gen 1 volt and most charging stations are more expensive per mile than gas. I only charge at home and when there is a cheap/free charger. Since most public chargers in my area are something like $0.60 KWH + $1~ plug in fee they are SIGNIFICANTLY more expensive than just filling up the volt, even with premium gas.
You do have to watch out when it comes to unplugging peoples ev's though. By default my volt would set the alarm off if you unplugged it while the car was locked. I turned mine off, other users may not.
But again the driver left a note, so it's all good in that specific case.
The charge tank on the Zero is the only ev I've ever seen that needs to be keyed on in order to start a charge. It's a truly strange choice. Would have made sense to key on to unlock the charge cap, but since the cap just flaps freely it's very strange. The whole charge tank system is strange. It should have been a replacement for the stock charge so you could have a charge tank in the belly pan and still have the power tank.