Battery Shelf-life

For an ordinary dry cell or battery , how long should it be stored or displayed in store shelves before it can be considered expired or not acceptable for sale? As we know, dry cells are not marked with any manufacturing date nor with expiry dates that can guide an ordinary consumer whether it is old or new. Voltage testing may not indicate if a battery is new or old, but an old battery will have less number of hours in use. Is this correct?