Earlier quoted context omitted.
Advertisers don't actually want to spend time picking YouTube channels individually. But they will complain if YouTube runs their ads against the wrong content. They have threatened to leave before. [1] Picking channels that are good for advertising is a service that YouTube does for advertisers. [1] http://www.businessinsider.com/why-advertisers-are-pulling-s...
Just out of curiosity how much leverage do advertising companies actually have?
Ad quality I am getting (long cheap ads on companies unlikely to be rich) confirm that.