“You know what—gyms make the largest chunk of their profit from clients who pay their monthly dues on auto-pay but never bother to show up and use the gym. The DVD-rental companies make a good chunk of their profits from late fees; the credit-card companies make a fortune on sundry fines and penalties; the airlines’ margins are highest on ticket changes and cancellations… So, the key to running a successful business in America is to sign up a customer and pray he’ll somehow screw up…”