It is not just a 50 USD card (or other similar values) that people buy and gift around? What this has to do with games?
I don't have any source for that, or even necessarily believe it (I don't disbelieve it either) ... I'm just pointing out what OP meant by that comment.
As a second effect, people don't think of things like iTunes cards as real money. Give someone $50 on an iTunes cards and, I suspect, it will see much less discretion than a $50 bill.
I was wondering about it...
Gift cards do not exist on my country, neither on my target markets, thus why I was kinda confused about it!