This interesting Wired Magazine piece, titled Why We Love Our Dentists, explores the unique relationship between price paid and perceived value. According to a recent study, two dentists will reach the same conclusion when looking at an identical x-ray only about half the time. Yet despite the fact that dentists are so frequently wrong (they can't both be right, can they?), people love their dentists more than any of their other medical providers.
The reason, according to the article, is due to cognitive dissonance, "the human tendency to react to conflicting evidence by doubling-down on our initial belief." The study's author Dan Ariely attributes our irrational love of dentists to the pain they inflict:
I think all of this pain actually causes cognitive dissonance and cause higher loyalty to your dentist. Because who wants to go through this pain and say, I’m not sure if I did it for the right reason. I’m not sure this is the right guy. You basically want to convince yourself that you’re doing it for the right reason.
The article has a few more examples of irrational behavior influenced by perceived value. Consider this study:
[R]esearchers supplied people with Sobe Adrenaline Rush, an “energy” drink that was supposed to make them feel more alert and energetic. (The drink contained a potent brew of sugar and caffeine which, the bottle promised, would impart “superior functionality”). Some participants paid full price for the drinks, while others were offered a discount. The participants were then asked to solve a series of word puzzles. [T]the people who paid