This doesn't even make sense. If you are charging per click (or view), you don't charge more because of number of visitors, you make more because Revenue=CPCCTRViews (and Views is getting larger).
Yes they do. The post you are replying to even explained that. If you tell the world "we have a billion users", more companies will decide to purchase advertising on your site than if you tell the truth and say "we have 400 million users". More advertisers competing for the same number of page views means they drive the price per view up, just as any other increase in demand without an increase in supply will drive up prices.
