My mother was so touched by her gesture that she decided to go back to the store and give the cashier a five-dollar bill to keep on hand in case the same happened to someone else if they didn't have enough money for all of their groceries.
The way we buy electricity today is like going to a store without seeing prices: we pick what we want, and receive an unintelligible bill at the end of the month.
As Bill Shope, an equity analyst at JPMorgan, puts it, the music store is a "loss leader" that serves only to boost sales of the iPod. It is as if record stores existed only to sell record players.