In my view consumption beyond need is always irrational. German Scientists also confirm this:
Researchers at the University of Muenster in Germany thinks a woman’s rational thought disappears when she goes shopping. They measured the electrical activity in the part of the brain which deals with common sense and rational thought in female shoppers. They discovered the part of the brain governing the emotions and pleasant feelings was in overdrive during shopping.
The scientists also found men experience a similar loss of control when offered the chance to buy electrical gadgets, fast cars and computer games.
Link via Diana