One potential for a totally autonomous vehicle are auto-share systems, where you use an app on your phone, the nearest available car pulls up, and drives you to your destination. Weight sensors would let the car know that you have a package or a bag of groceries on a seat and remind you to take it with you. Basically, you wouldn’t have to own a car, but you’d still be able to use one when needed.
The cars would be in constant use, and if they are electric, reducing pollution. The cost of ownership is substantially reduced and there would be fewer cars on the road.