Who doesn’t like a freebie, from the packet of Haribo sweets included in my Wiggle order, to free Wi-Fi at the coffee shop? An experiment In Dan Ariely’s book, “Predictably Irrational,” illustrates this brilliantly.  Participants were asked to decide between spending 26 cents on a luxury Lindt chocolate truffle or spending one cent on a lower-quality Hershey’s chocolate kiss.  Those running the …