Re: @ tannin
"People wouldn't continue to purchase advertising if it didn't pay more."
Simply not true. No one has any idea how much advertising actually pays. All of the employees on both sides depend on advertising 'working' for their jobs to continue to exist, so they report accordingly. Nobody wants to admit that they ate a Big Mac because they wanted to, so if you harass people with questions, they'll claim the advertising made them do it.
And that's just the base layer. That doesn't account for the systemic fraud, routinely exposed on sites like Facebook, where they run bot armies to click links and likes to justify the advertising costs they charge their customers.