Walking and biking in the city center with lots of green areas.
No cars means clean air and safe traffic. Air pollution from cars is a silent killer.
I agree, and in fact I do this (park at BART in the East Bay and ride it into SF). The problem is, no one is advocating constructing these systems where they don't exist. They are advocating a direct ban (or prohibitively high tolls and parking scarcity) to prevent people who live outside the city from entering it at all. With maybe some handwaving about bicycles, or an assertion that walking 4 hours a day is good for you. Some of the same people are even advocating that we eliminate the existing parking at suburban light rail stations!
Because clearly what we need is even more pressure for even more people to pay astronomical rents.
My city's (Prague's) administration actually supports this a lot, but since the city districts (and not the administration) actually hold power over what gets built in a specific district, and no district wants a big parking lot, the situation remains as bad as ever.
Or worse, bad compromises get through -- for instance park at the very edge of the city and then walk 10 minutes to a bus which takes another 15 minutes before you reach any subway station. A great political move to destroy the whole idea.
In otherwords, I still park in the city but I also get paid more to compensate for the costs of commuting, because it is still the best option available to me.
If they shifted the parking to the fringe of the CBD at various transport hubs and removed it entirely from the CBD then there would be more usable space for city inhabitants, uninhibited public transport and separated foot/bike traffic. All much better options than a car doing nothing on prime real estate for 8 hours a day.
But given the income required to live in the city vs. in the surrounding area, I'm skeptical that we should be creating more playground for the well-heeled inhabitants of trendy neighborhoods at the expense of people who need to live car-sized distances away from the CBD (and transit hubs) to have decent homes at their income levels. Maybe if we thought the resultant construction could house at least as many new residents as the drivers it displaced.
So yes, transportation hubs!
I live in Boston. It snows here and I do often buy more than one bag of groceries at a time. Fortunately, I just walk two blocks down the street and go into one of the two grocery stores that are right there.
Compare where I grew up in southern NH: it snows there, too, but the nearest grocery store was a 20 minute drive, so of course I would drive there. Rural NH is not a city, though.
I was only there for the Superbowl and never actually walked one, so maybe it's not so convenient.
What's the big deal?
The problem is that personal car ownership with our current technology does not scale up, when taking into account of environmental impact. Nor when you reflect on just how much public right of way we've given up to infrastructure for cars. Nor when you think of how many people die of automobile accidents. Nor or the impact cars have on living in social communities.
Groceries? I walk. Have one option a 15-minute walk away, and two 25-minute walks away. I do 3 to 4 bags at a time, not a problem. I also have subway/bus literally across the street, and right next to highway for when driving to clients makes sense -- but usually can get to them via mass transit (subway and bus) so long as they're in certain areas within about 20 miles (32km) from where I live.
Still own a car, but it's only for fun, not necessity and I never use it for errands. If it wasn't for fun, I'd not bother with owning one.