It'll be still on the shelves, some one will buy it and eventually someone will not be bothered (or maybe not even notice) that parts are missing.
Restocking returned goods "as new" with damage or faults is very common. This is the primary reason I avoid buying in DSG Retail group stores (Dixons, PC World, The Link, Currys) having bought stuff "as news" shrink wrapped, sealed, only to find it "used" and obviously a customer return on unpacking the product at home. Be very wary of places that insist that
*everything* is returned when you reject goods due to faults or damage.