In high status areas the local government and landlords are much more likely to plant street trees to ensure dismounted people can comfortably walk. In neglected areas there are less trees and the sidewalk is crumbling or abruptly ends.

If SUVs are speeding along at 54 MPH right next to the sidewalk, their wind hits you, their noise hits you, and some asshole drivers intentionally drive over puddles in an attempt to splash pedestrians.