True, but if you live near Presidio in SF or Prospect Park in Brooklyn (as examples) you can totally walk to a forest! And in many places where people own cars

True, but if you live near Presidio in SF or Prospect Park in Brooklyn (as examples) you can totally walk to a forest! And in many places where people own cars you and just drive 5 or 10 minutes. But clearly these circumstances are far from universal. Most people are lucky to have a half-decent park within a 10 minute walk.