I think I remember seeing threads on this before, maybe last year, and someone pointed out that at least for teens, a lot of gifts just are more expensive, especially if they aren't into books. I think a similar idea was discussed in the recent thread about equal giving among, say, one's grandchildren--you can get a 5-year-old a great toy for $10, but if you feel you can then only spend $10 on the 15-year-old, it's probably not going to buy them a gift of comparable "awesomeness" to the 5-year-old's. So people should at least think about that before they start buying gifts.
I don't see anything wrong with the charity in charge having guidelines or limits on what the kids should write down; I mean, if you think about it, the wish from the kid in the OP for a job and a house for his family isn't exactly something a person can buy for them, either. It makes the Xbox look quite reasonable in comparison. So it seems like this charity didn't have anyone nudging the kids in a particular direction, and what that can result in is wishes that simply aren't going to be fulfilled--whether it's something no one can grant, like a job for a parent, or just something outside the price range of most people, like a video game system. I certainly don't think the kid was rude to wish for the things he wanted; if anything, the charity was unwise to not have rules about tempering the kids' requests to make it more likely they'd be fulfilled.
I think if you (general) don't like the items on the card, put it back and take another; or, if it's too late to take another, try to fulfill them as best you can in the charitable spirit of the situation. Even if you get the kid "generic" stuff (because the stuff they asked for was too unrealistic), at least they're getting something, when before they would've gotten nothing. If it's just going to cause you stress and angst to fulfill the charitable donation, just don't even get started with it.