You’ve just come home from the gym and discovered that your teenager cleaned out your stash of energy bars. Drat. You decide to order a new supply of bars online. You usually buy Clif Bars, so you type the brand name into Amazon search — but just as you’re about to click the “Buy Now” button, you notice an ad for Quest Nutrition bars at the top of the search page. The bars look appetizing, they get multiple-star customer reviews and — best of all — you can get them at a bargain price. One click later, Quest has acquired your business.