I am a firm believer in doing the "right thing." What is the right thing you ask? That is to look at the situation from all sides and stick to our companies mission of providing fair, honest and excellent service. Unfortunately, almost everyone here recommended rewarding bad behavior, and the nice customer that asks will get nothing. This is why these type of customers threaten all of us--because many companies have trained them to complain and be unreasonable--thus perpetuating the cycle and making this not about the one customer but all your customer issues.
The web works both ways as Gabriel so eloquently points out. Almost everyone here looks at this one situation and says it is not worth their time. I say you must spend the time on these situations or you will lose every time and what is the point of warranties, supervisors, managers or rules if you do not stand by them when it is completely appropriate. All of the people that you just "pay and move-on" will tell everyone to fight because you do not take a stand and will give in. The unreasonable people that we are talking about do not take into consideration that you gave in. They will say bad things anyway. It is as naive as to assume that if you leave a dollar bill on the passenger seat, that no one will break a car window for a dollar. You do not realize that they do not weigh the cost of your window against the dollar, it costs them nothing.
I strive to imbed my mantra into our CSR's that we should try to turn every situation into a win-win-win (customer-company-CSR) and if it is not possible, that does not mean someone or anyone has to lose. I do not believe backing someone into a corner is a good idea even when in the right, I want to allow them the opportunity to gracefully exit so I preach to our staff to offer some consolation, an olive branch if you will, even when we are totally within right to do nothing in order to show that even though we are in the right we also care enough to compromise without compromising our principles.
And, when they do post do exactly what Gabriel stated. This will pay off more than than you can believe and if you do not you will spend much more time and money just giving in.
Gabriel I stand with you.