It's not even just major cities either- I'm frequently in a college town in Illinois and parking downtown is a nightmare, and can easily add 10 minutes to your trip time, AND it's paid. Visiting a city I'm not familiar with can add some stress too as you don't know the best parking, unlike cities you are familiar with.
NYC has problems of it's own (trains are generally reliable, but tend to have delays right when you need them), but for $33 a week I can get to most major neighborhoods in 30 minutes, walking straight to my destination. Add in $40 for a couple cabs when I prioritize a quicker trip, and I have amazing access to my city for less than $100/week.