Constable
I do agree with you, sidewalks should be mapped adding the sidewalk=* tag to a road, they shouldn't be drawn as somebody did here. Have a look at the history of those paths and ask directly to the mapper who added them. In case he'll not answer you'll have any rights to ask the Data Working Group (http://wiki.openstreetmap.org/wiki/Dwg) to take care of the problem. I doubt he'll read this note.
Cheers