I want that!

Apparently, blatant consumerism shows up right around age four.  My wonderful child is usually not one to covet what others have.  He is, by no means, perfect; and he will throw the occasional fit in the store if he doesn't get what he wants.  But recently, he has been wanting everything.  Every commercial that he sees on TV leads to a chorus of "I want that!"  I guess it is a logical step in child development, but it is really grating on a person's nerves.  Just hearing him say over and over and over....I want that, I want that, I want that....it makes me want to show him all those in this world who really don't have anything.  But, I'm afraid the trip to see starving, homeless, or orphaned children wouldn't have the desired effect on an almost-four-year old.

I don't know how to counteract the consumerism, especially during the Christmas season, when he is going to be getting a lot of what he wants from his grandparents, aunt, and the rest of the family.  How can I teach him that his worth isn't wrapped up in the 'things' he gets?  How can I teach him that it really is better to give than to receive?  How can I teach him to be thankful for all that he has?  And if all that fails, how can I teach him to stop saying "I want that!" at the top of his lungs?