The poor old consumer! He'd have to pay a great deal more if advertising didn't create mass market for products. It is precisely because of the heavy advertising that consumer goods are so cheap. But we get the wrong idea if we think the only purpose of advertising is to sell goods. Another equally important function is to inform. A great deal of the knowledge we have about household goods derives largely from the advertisements we read. Q:What does advertising do with the products we already know about?