I've just phoned dh on his mobile and this is what he has done. It's not a small shop but a big supermarket.
His intewntions are good. He has given them some sort of picnic dinner to eat in the car and then gone off to do the shopping.
I've told him I strongly dissaprove.
Not only will they spill food all over the campervan but they're highly likely to start messing about with the handbrake and pressing buttons (and the horn) on the dashboard.
I'm amazed he thinks this is OK.