I get most of my grocery shopping delivered, or I go to the supermarket in my cargo bike, dump it all in the front, and ride home. You really don't need a car for this stuff at all.
I live in Parisian suburbs and stores are all less than 10km away, I have never had trouble getting anything.
If I need something larger / heavier (say, cinder blocks and cement) I just rent a truck for two hours and get all the heavy shopping done in the time frame.