I’ve seen this 2 ways:
1) we do this when visiting friends. The have just a regular 110 Outlet. No big as we installed a Victron Multiplus that can pull from batteries to help us run the microwave etc
2) The RV park we leave our coach at in the summer tells us, and we’ve seen it, EV cars come in late night and plug into a site after hours and charge. They try and get up early and get out, or claim dumb that they didn’t know it wasn’t “legal”. The resort at the lake has random cars that will show up and have extension cords ran to a cabin, they’re not guests. People will just plug in, walk down to the beach and play all day, while stealing Electricity