I didn't get it either...especially with the mileage he drives and the alternative options that are available in SanFran....Uber, car share, public transit, bikes....I mean San Fran is like the nirvana of a place to not need a car.
If all you want to do is hang around SF, sure. But I for one find that paying a premium to live in CA just to live in a city is ridiculous. You have wine country (many wineries offer free or $5ish tastings), gorgeous beaches, mountains, redwood forests, Sequoias, Joshua Trees, Lassen Volcanic, and even some ridiculously fun caves far up north (almost Oregon). Zipcar will cost you $80-100 for a day's use (and demand on weekends might be ridiculous). At 4 days/month (let's say 2 weekend trips camping), that's 3840-4800/year. If you have a place to park it (e.g. already live in place with garage), you might as well buy a car.
Leasing, however, is a ridiculous concept and the Fit we test drove did not feel like it could handle hills at all, making it a strange choice for SF. To each their own, I guess.