Starbucks Economics - Solving the mystery of the elusive "short" cappuccino. By Tim Harford

Marketing is about selling the right product to the right customer. And sometimes, this means sabotaging your lower-priced products so they don’t attract customers who are already buying your more expensive products. One restaurant even goes as far as hiring a rude waiter to man the section with a cheaper menu in order to discourage diners from sitting there.