I would think that gift-giving is an extremely old tradition, but much of these gifts came as personal services (I fix your fence or feed you), or hand-made memorable things. The idea that only brand-new, shrink-wrapped things are any good, and that you should spend all your money to buy these things of certain types for all occasions for your colleagues, neighbors, relatives, friends, etc. etc., seems quite new and following from the commercial culture. In Russia which I was so fortunate to observe before the commercialization (though not quite shielded from commercial memes) these tendencies were much less pronounced.
Another reason for expensive wasteful activities, IMO, is the mundane memetic pressure. Just like fish and peacocks grow their tails out of all practical proportions, many cultural traditions tend to exaggerate their symbolic messages, and put extreme amount of effort into cultural rituals. All advertising has to do is to guide this energy a little by suggesting that wasteful practices should be based on buying stuff (as opposed to physical activities, sacrifices, and other non-consuming activities that find little advertising interest). The conservatism of tradition seems to go hand-in-hand with the conservatism of industry interests and investments.