It reminds of the calls I sometimes get telling me I have something wrong with my Windows computer, If I'm in a playful mood I string them along for ages before telling them how clever they are considering I don't even have a Windows computer.
A friend of mine used to work in a call centre and occasionally he would get one of those impossible customers who is always complaining and can never be satisfied. With some of those callers, he'd put them on hold and go for his lunch break.