Happens all the time. This can be because of incomplete knowledge of the product or service. It could also come about because of changing market conditions. The couterpoint to your argument would be that you always get what you pay for, which, of course, is correspondingly false.

Let's take a recent example from this hobby... the Canadian Silver Slipper diecars. They're in the books at big values (based on what the authors thought was correct information at the time), and people tend to believe what they read. Huge prices were paid for these chips and those who don't read The Chip Board didn't find out the story as quickly as those of us who do, which created a knowledge differential. Well after the story unfolded right here on TCB, a $1 Silver Slipper chip sold for $12.30. Two days later, one sold for $202.55. Today these are selling for about 5 bucks. Same thing's happening right now with another group of chips.

Other times a find might render a chip that someone paid $5,000 for relatively worthless. It's happened with more chips than some like to think about.

It's well and good to say that the gentleman who paid $202 for that $1 Silver Slipper was paying was it was worth to him, but in the real world you can see that this "truism" isn't worth much... most would call that "getting burned."