Tires are like groceries, all the suppliers want to get rid of OLD inventory before it spoils. The new inventory is always placed in the back of the rack, and usually, the older the merchandise, the cheaper the price. If the store does not have what you want in inventory, they will charge you extra to get them. This is what is called "basic inventory control process!"

BTW, you should get 215/65/15 tires for best handling, control & speedometer accuracy.