If you return with <80%, what happens? Do they charge a flat fee or by the kWh? Most cars will taper charging speeds as you approach 80, 90 %. And then you have to drive from the charger to the car rental place. Hmm.
Yeah, I dunno! With gas, they would typically just charge you some exorbitant price per gallon, but if it's just for a gallon it would only end up being 8 bucks or something. I have no idea how they deal with electricity, but I could imagine the penalty being pretty high if it means they can't turn the car around for an hour or more.
