What's in my car? Lemme think. Back seat: for TGS I have a car seat, some small toys, a full size blanket and a jacket. Under the front passenger seat is a large package of oyster crackers and a small container to put them in. Also a small bowl in case we have Ozzy-dog with us and he needs some some water. Oyster crackers keep TGS busy when if I take him into a grocery store and keep me from having to buy snacks every time.
In the far back of my SUV there are 3 laundry baskets lined up. 2 are empty for corraling purchases so I don't always have to bother with shopping bags. The third has two full changes of clothes (one for me, one for TGS), a couple of diapers, wipes and plastic bags, a sweater for me, an emergency gallon of water, and a few shopping totes.
Center console has phone charging cords, and a couple of ziplock bags - one has KN95 masks, the other contains a few granola bars and assorted hard candy. Small trash bag between the console and my seat. Glove box has gloves and vehicle manuals. Driver door pocket has spare sunglasses, spare reading glasses, a whistle, and a bag of assorted coins.
I've always had a lot of stuff in my car - not trash or junk - just "stuff." I remember Rhoda Morgenstern (from the Mary Tyler Moore Show) once remarking that she thinks of her car as a traveling purse. Totally understood that.
My car is neat, but not anywhere near as empty as when I drove it home. On the contrary, it contains many of the little things that make driving comfortable for me, including many items LAFD recommends people to carry in case they're caught away from home during an earthquake or other disaster.