Off the top of my head I have chargers, sunglasses, brufen, snacks/water/hand gel, a giant umbrella, assorted maps and a compass, a change of clothes or two, boots, IFAK, shovel, a couple of flashlights and some tools. Most of these things are used frequently enough that it would be massively annoying not to have them, and some if you need them then it’s too late to get them from somewhere else.

+ coat, toys, diapers, paper towels, mirror, first aid kit.

And a saw, needed that more than once. How is a passenger in a self-driving car going to deal with a tree fallen across the road?

- earthquake kit (water, energy bars, flashlight, first aid kit, foil blankets, ...)

- mess cleanup (paper towels, wipes, windex)

- small tool kit (leatherman, couple wrenches, battery post brush, duct tape)

I think there’s more but that’s off the top of my head.