I attended a great concert in Vienna this Friday night. Afterwards, on the way back to the apartment of the friends I was staying with, we passed a cafe where we had drinks a couple of times on previous occasions. Much to my surprise, the cafe was closed. I asked my friends what had happened - surely a location like this with thousands of concert goers passing by every night must be a gold mine? The tale my friends told was not only sad, but provided insight into an often overlooked tendency in human decision making: Our unwillingness to accept proposals we perceive as unfair, even if refusal comes at a personal cost to us.