Note that even in Tokyo, which is often held up as having some of the best public transit in the world, around 30% of households own a car. Around 12% of trips

Note that even in Tokyo, which is often held up as having some of the best public transit in the world, around 30% of households own a car. Around 12% of trips there are taken by private car. That suggests that there are still a significant number of cases that are not covered well by public transit. For example I don't see how lockers solve the issue of multi-store shopping trips that was mentioned in the comment above. The locker would give you some place to accumulate the purchases from each store, but unless you could carry them all simultaneously you'd still need to make multiple trips between the locker and home to get everything home. I suppose you could use public transit when going store to store accumulating things in the locker, then use your car to move everything from the locker to home in one trip. That's probably optimal. While going store to store you don't have to deal with finding parking at each store because you are taking public transit so might save time and money there, and you save time and money by getting your stuff home in one car trip instead of multiple transit trips.