At the risk of hurting my case, advertising is probably not quite as good an example as you're making it out to be. In particular, competition between two bran

At the risk of hurting my case, advertising is probably not quite as good an example as you're making it out to be. In particular, competition between two brands of the same product need not be a zero sum game. If every beer company runs ads in which beautiful women fawn over a guy drinking beer, the outcome might be that every company sees higher profits than in a world without any ads at all.