Poly Feet ?

It occurred to me after a weekend of watching Keeneland races, that there might be a POLY FOOT. There are mud feet and turf feet, so why not POLY feet. Has anyone been trackside and looked at the feet of the horses that have done well there ? Also, has anyone been paying attention to the poly track at Turfway or Woodbine and noticed whether there have been any changes in the surface during the racing season that either track maintenance or weather has done to it ?