Should they put it up our of charity and the good of their hearts? No, absolutely not, but as consumers, we should have the choice when we do and do not pay, and automatically opting you into payment, whether it's a monetary payment or my privacy, is removing that choice.
There are many websites which openly ask you to please disable your adblocker when you access them, and willing participants should do just that. Ars Technica did something like this last year some time (http://arstechnica.com/business/news/2010/03/why-ad-blocking-is-devastating-to-the-sites-you-love.ars), and I feel that this is true of most things. Whether it's a news site I like, or a particular streamer for a game, if I find the content useful and I wish to support the person, I disable the blocker on that domain.
What I don't think is that any site I go to automatically deserves the same treatment. It's an assumption that by visiting that I am interested in a long term investment, whether it's via ad networks or subscription.