I care for it because driving fucking sucks. I'd rather have my car display a hundred ads to me if I don't have to physically take the wheel during your average rush hour in DC.
I like driving but I don't live in an area with shitty traffic so that probably changes my opinion. I like being in control.
Moreover there have been roadside billboards for over a century. There have ads on the radio for decades. Bumper stickers, ads on trucks and commercial vehicles etc The driving experience was already full of advertising before Google started dreaming of self driving cars...
Yeah there is already adverts prevalent when I drive, some which I can avoid and some I cannot. That doesn't mean I have to accept more advertsing from somebody else when I am out.