Anyone who runs a store knows that simply putting prices on an item and waiting for a customer to pay it, is hardly enough to be able to run your store and make a profit. Knowing the buyers needs, and keeping track of the current prices of the local area help the shop owner get the best prices from his items. Also, a little knowledge in the bargaining tactics can help keep him from getting ripped off by those who wish to bargain the prices down towards their own desireable levels.