The rights holders have effectively said "you can watch this for free as long as we get the ad revenue". Theoretically, if there was some way of preserving that ad revenue while committing that infringement, I would assume they wouldn't care about the infringement. They're just using the infringement as a tool to preserve the ad revenue.
What you're worried about is the converse, if there is a way to avoid infringing on copywrite while bypassing ads (which there is, ad-blocking), then there's no infringement to use as a tool, then they're going to want to make ad-blocking illegal. It's not hard to predict that's coming, especially in Europe given Article 13 last year.