WHY STUDY ECONOMICS? Great Day by Day, for one. Or answer this question: There is a room full of pistachio nuts. People may eat as many pistachio nuts as they want in the room, provided they eat them only in the room and leave all the shells in the room. Outside the room is a vending machine, where a bag of pistachio nuts will be yours to eat as you like and clean up as you like, for a dollar. Will the vending machine ever be used?