You're correct, the ad industry is zero-sum. The end goal is as simple as it looks: support a new medium. First it was newspapers and magazines and mail, then

You're correct, the ad industry is zero-sum. The end goal is as simple as it looks: support a new medium. First it was newspapers and magazines and mail, then the radio, next television, and finally we've landed on the web. And in the future there will probably be another new medium that ad dollars shift to. The strategy is simple -- rip market share away from the competitors. And it's working. Why? Because you can more aggressively target intent, track results easier, and garner more impressions since the inventory is both cheaper and plentiful on the web. [1] Source for zero-sum as industry claim: https://www.bloomberg.com/news/articles/2014-03-03/advertisings-century-of-flat-line-growth https://www.bloomberg.com/news/articles/2014-03-03/advertisi... (TL;DR ad spending as % of U.S. GDP has remained relatively constant since the 1920s)