But there is another issue I find very interesting. It seems that the company believes in fairness.
You can buy there a lot of coffee varieties. Some of the coffee beans are offered in open barrels. You can fill them in a bag and grind the beans in a grinder next to the barrels.
The beans have different prices, relating to the qualities. The cashier doesn`t know what quality is in your bag. Hence you write a code number on the bag defining quality and price of your purchase.
In theory people could confuse the prices by accident or not. In theory they could write the code number of a lower priced coffee brand on the bag and save some bucks.
But this wouldn`t be fair. Neither would that be cool. Therefore people generally write the right price on the bag and pay the right amount. At least Whole Foods Market is trusting their customers, maybe because they know that their clientele is cool.