Why would Best Buy sell counterfeit iTunes gift cards? Granted, we've all heard of bad stories about Best Buy but there's no way Best Buy would intentionally partake in a crime.
It's called a loss-leader, and retail stores do this all the time. It's just usually quite so obvious because the gift cards have a value stamped on them so you can compare the purchase price to the value.
Basically, a loss-leader is a product that a retail store sells at a loss in order to bring customers into the store where they will (hopefully) buy enough stuff (at a profit) to make up the loss. In the case of the gift cards - you come into the store and buy a $100 card for $80. Best Buy is out $20. However, in a number of cases you are going to turn around and buy an Apple product worth about $100 from Best Buy, which they are selling at a profit. I don't know the BB markup on Apple products, but it's probably not much. Say they come out even.
However, since you have already started shopping you are (statistically) probably going to buy more non-Apple stuff. And that is where Best Buy makes their profit. It's not on the Apple stuff you bought with the gift card, it's on other stuff that likely would not have bought otherwise.
Also keep in mind that Apple is probably also probably discounting the gift cards to Best Buy, so that $20 loss is going to be less than you might think.
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Supermarkets are the biggest users of loss-leaders. Once upon the time it was milk. All milk was sold at a break even or at a slight loss. Which is why traditionally milk is found at the back of store. Everybody needs milk, so you bring customers into your store with your great price on milk. And make them walk by all the other stuff that they had forgotten that they needed. That is where the profit was made.
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Once upon a time I worked at a MacDonalds restaurant. The basic burger was essentially the loss leader. But along with the burger, you ordered fries and a drink. The fries were highly marked up, but the fountain drinks were a license to print money. At that time it cost us something like 2 cents to put flavoured sugar syrup (Coke,etc) into a cup that we sold for 49 cents. I suspect that the scale of the markup hasn't changed much over time. That's the real profit centre at a fast food joint. That "supersize" value option you get? Sure you get 50% more pop for only 20 cents. But it costs them something like 1/2 a penny to "supersize" your drink (some of the cost is the labour to bring it to you and ring it in. Same labour cost regardless of the size).
Wish I had a business with that kind of mark up, eh?
