Path is a more ambiguous tag than footway=sidewalk is. Sidewalks are exclusively footways right along the side of a road, while a path or footway without specific tags varies in its purposes. Looking at aerial imagery again, specifically comparing the Bing Aerial to ESRI Clarity, this doesn't seem to actually lead anywhere, and it's rather an old alignment of a footway or authorized vehicle accessway that used to directly connect to the sidewalk along Las Vegas Blvd but now dead-ends at a retaining wall.