We've entered no contract, you have no right to dictate any terms to me at all. Period.
If you'd like to chose to not display your content when I have a blocker enabled, so be it, I'll leave and never come back.
But to make an assumption that you have any sort of control of my time and attention is insidious. Fuck off.
I'm not stealing when I drive by billboards without reading them, I'm not stealing when I turn my tv off when commercials come on, I'm sure as fuck not stealing when I block your ads.
If you'd like to enter into a contract that actually tries to enforce your ludicrous idea that my attention is implicitly yours to demand, I'd suspect you'll find very few takers...