Indeed. In NYC I do 98% of my shopping by walking. I can reach my doctor by walking. My daughter used to walk to school because it was a 10 minutes walk (and an excellent school).
That would be impossible in a suburban setting; at best, one of these destinations would be within the theoretical waking distance, but without the walkways.
Absolutely. There's a reason body fat percentage in New York City is so much lower than anywhere else in the US!
> That would be impossible in a suburban setting;
Not necessarily true. The "village center" idea Jim Rouse used in his design of Columbia, MD could be used to solve the problem.
All of these things are within walking distance if you live in Columbia's village of Wilde Lake (and, of course, your health insurance covers the primary care physicians in walking distance).
I'm guessing you're thinking of typical "stroad" suburbs, but alternatives are possible and do exist.
Unfortunately, the suburb has to be the product of planning like Columbia. Typical "emergent" suburbs turn into unwalkable ones.