They can't be deleted by accident. Presumably using one will delete it. The WoW Token was announced to become available on April 7, 2015 in the Americas region and appeared to have an initial default Auction House price of around 30,000File:Gold.png, but the price dropped below 25K within a week on many realms. The ability to use a WoW Token for Battle.net Balance spiked the AH price up dramatically.