Last year, more than $8,000,000,000 was wasted on these cards. Not in the value spent, but in fees and breakage. When you give a card, if it doesn't get used, someone ends up keeping your money, and it's not the recipient. People spent more than eight billion dollars for nothing... buying a product that isn't as good as cash.
Along the way, we bought the story that giving someone a hundred dollar bill as a gift ("go buy what you want") is callous, insensitive, a crass shortcut. Buying them a $100 Best Buy card, on the other hand, is thoughtful. Even if they spend $92 and have to waste the rest. ~ Seth Godin
I don't have the figures, but logic dictates that this doesn't just apply to gift cards in the US.