There are of course many many cars on the road, most occupied by one person.
Many people are out of shape, it seems, and are exhausted and out of breath after a short ride.
So I think it comes down to, for a lot of people, a very personal view of their world and what they think works for them. Certainly people in our society are completely sucked in by the notion that cars give you freedom and anything else is too much trouble. Sad, because for me the reverse is true, and if they would only try an alternative, each individual would find their life so greatly improved. Regarding transporting things by bicycle, it's amazing what can be carried in a backpack or bike basket. And elderly friend of mine has never had a car and bikes everywhere.