You could totally set up your own site and charge people to view it, or strike your own advertising deals for your own site's content.
But then you'd probably not get any of the benefits of being on the YouTube platform (discoverability, advertisers already on board, targeting etc), so it starts to make more sense when you consider what the platform is giving you for "free".
I mean, you could, but the point is that we're forgetting that ads as a monetization model are taking away our freedom to price our products as we choose.
It would be similarly ridiculous if all apps in the App Store were free and you were paid some small amount per app-invocation that you had no control over.
