I can' t tell you exactly what' s happening, but one of the woods I hunt has a similar pattern. I find nearly no rubs, but a pretty good number of scrapes. The rubs I do find are generally on small, young trees. But, the woods always has a couple nice bucks and is definately worth hunting.
This particular woods is a public pine plantation, and has lots of small trees growing on the forest floor between the mature stands of pines. The only reason I can see for the reduced rubbing activity is that most rubs wouldn' t be very easily seen by other deer.

Anyway, I can' t explain why, but I would say it should be worth hunting. Go ahead and hunt the scrapes and see what happens, then adjust if you need to. I' m not an expert, but I would start at the best sign I could find and see what happens.

peashooter