My big birthday buck I shot last week walked right down a path in between a standing corn field/edge of the woods....and a logging road...about 15 yards inside of the woods. Along the said path are at least a dozen scrapes...and at least twice that in terms of rubs. For some reason the deer in that woods don't walk down the logging trails. He walked down "scrape road" as we now call it...right to me.
Long story short.....hunt good rub/scrape lines NOW...before they abandon them. I wouldn't worry too much about a lone scrape...with a rub or two near by. I like hunting scrape lines...where every 10 yards there are rubs and scrapes everywhere.