In general, I think mapping the pavements (sidewalks) separately is a better representation of reality, and allows for better pedestrian routing and tagging properties of the pavements. Sometimes it has to be done to capture what's on the ground, and then things look inconsistent if you don't do it fully in an area. If I recall correctly here, some of the paths round the cross-roads were already mapped separately here, but not all of them, so I completed some of the missing parts.