We could significantly improve it now with more Zipcar type apps (at least in cities where people live close together) but the most people want guaranteed access to a vehicle at 8am and 5:30pm weekday situation isn't easily solved just by making them mobile when not in operation. Nor - at least in the short term - is people's tendency to use cars, and especially cars with no previous owners, as a status symbol (many people could save more of their income not buying new models and premium marques than allowing it to be used by someone else at weekends and some evenings, but they choose the car that takes up more of their disposable income all the same)