Everyone seems to be reading this in the most literal way possible and complaining that the numbers aren't real, or that advertising doesn't work that way, or s

Everyone seems to be reading this in the most literal way possible and complaining that the numbers aren't real, or that advertising doesn't work that way, or somehow thinking this is some sort of recommendation for an advertising based business strategy. It's not. The point is simple: For the same unit costs, if you get your payment cycle time down, you will make more money. It's a mathematical example showing what happens in extreme cases, so that it's easier to spot the trend. Nothing to do with advertising specifically.