Exactly. As things stand now, they pretty much need a banking account. How many 13-year-olds have banking account? Not many.

And what OP fails to mention is, you can already go to any retailer and buy an XBOX Live card for cash, which is then used with Microsoft. Buying a $20 Xbox Live Card at WalMart is a hell of a lot easier than figuring out how to buy bitcoins for the first time, especially if you don't have a bank account.

This move is merely to encourage current holders of bitcoins to spend them with Microsoft. A large portion of bitcoin enthusiasts are nerdish young men, so of course Microsoft will do something like this to target them.