Though to be fair, over the years I've mostly avoided the most intrusive ads by failing to install Flash.
Readers have a direct relationship with publishers. Advertisers have a direct relationship with publishers. But readers do not have the direct relationship with publishers, and indirect access to readers is what the advertisers is paying the publishers for.
It seems to me that the idea that sites are taking advantage of users tendency to use default settings has about equal footing with the idea that users are taking advantage of sites when they don't use default settings.
There's no need for a paywall to work around that ambiguity, just return different content to registered users (and explain up front that the page is provided in exchange for the user viewing the ads).
I'm not sure there is one, which is one way the internet flips the script. I'm not entirely sold on the idea that using adblock is unethical or stealing. Seems much closer to something like a donation box, where the "seller" puts the goods out there and hopes that the "buyers" will give money (in the form of clicking on ads or at least not using adblock).
It's a loose set of rules, the internet, but no one is really obligated to play buy those rules. The question arises, what does the internet look like if everyone uses adblock? What sites disappear that we care about and what disappears without a complaint? And what works in ways we wouldn't have imagined before?
And I've been an adblock user, but I'll admit that I've stolen content from sites by using adblock.
The "seller" gets to decide the "price", the "buyer" can agree to the "seller's" terms, attempt to negotiate, or decide not to partake in the transaction. The internet at times allows that script to flip.
I'm still not sure where the ethical boundaries lie, even as I've typed this response I can't decide what is right and what is wrong, or to what degree.