Theres a good chance that the tag was supposed to be replaced when the price went up, and then this “sale” started sometime after, dropping it to the old price point. I would see it most often in the health and beauty sections of my old store, because they have so many small tags, sometimes the employee whos changing the tag cant find a specific one that needs changing and just tosses the new tag instead of working to find it.
Yup, we did the same with CS 1.6