As a kid, our scout troop had a fundraising deal with the local Schwan's distributor, they would bring in a delivery truck full of ice-cream and we'd sell it at

As a kid, our scout troop had a fundraising deal with the local Schwan's distributor, they would bring in a delivery truck full of ice-cream and we'd sell it at a local festival, and then pay wholesale for what we'd used. Anyway basically there was no power at the festivals, it was usually just a parking lot at a local highschool, so they'd plug it in overnight. Not sure whether they had batteries/etc, but they were perfectly fine being out in a hot parking lot for 16 hours, no problem. And we were constantly in and out of the trucks selling ice cream which is not what a delivery truck was designed for.