Let's say you get a gift card worth $50, spend $29.82 of it and then put it in your wallent where it is promptly forgotten. The next Christmas season while out shopping you discover it again and you ask, "I wonder how much is on that card?"
So, you call the 800-number and in seconds you find out. They tell you the card is worth about $4. Somehow, that doesn't sound right to you so you call the 800-number again and go through the process of talking to a real person....
The 800-number, the computer system that supports it, the people who work in the department to support gift cards, etc is all overhead that is, by law, allowable justification for charging fees associated with gift cards.
A lot of people think that companies like gift cards, and they DO. But, there is a degree of accounting hassle for them. They cannot count a gift card sale as a sale until it is actually redeemed. So, by law, if they sell $4 million in gift cards in a year but only $3 million is redeemed, that $1 million difference is considered an asset, which is taxed differently than sales dollars. All of that has to be accounted for and balanced.
I read somewhere recently that last year alone Home Depot had something like $42 million in unredeemed gift card dollars on their books.