My life is so boring, somebody might say. I'm so miserable. I've got no options left. I must go shopping. This truly can be a solution. Some doctors even use term shopo-therapy for their innovative methods of treatment.
Speaking seriously - it can help you. Did you feel yourself somehow different just after purchasing some item? Was it nice feeling? I'm sure it was, if it was just ordinary stuff. But you can imagine what you'd feel if you get a pair of Levi's, or a nice diamond ring, or a car, whatever. You'll rise your mood up to top possible level, or in case you were depressed, it will cheer you up a bit.
What so interesting in buying stuff, you can ask. What exactly makes you feel better? I guess this instinct of owning things has great history. Whoever you are, you must have your own possession to be sure in future. But people are trying to get all stuff in the world in their possession. And now we are dependent not only on buying stuff, but on brands too. It's a disaster. How can one man, who invented riveting process, sell pants at double price comparing to others with same quality and durability. I guess nowadays people are to lazy to work by themselves. You can browse news about record studio who oblige divorced mother with three children to pay one million dollars for downloading several songs from the Internet. And they didn't make those songs, they just recorded it...