"One study of how memories influence consumption explored the phenomenon whereby people who have truly enjoyed an experience, such as a special evening out, sometimes prefer not to repeat it. We might expect that they would want to experience the physical consumption of such an evening again; but by forgoing repeat visits, they are preserving their ability to consume the pure memory – the concept – of that evening forever, without the risk of polluting it with a less-special evening."
-- Dan Ariely (Predictably Irrational) and Michael I. Norton:, MIT Tech Review, via
P.S. And then I go to Amazon for the link to Arieli's book, and see it right there on the home page. Spooky.