I've long wondered what would happen if, say, NYT sued me for blocking their many ads (despite being a paying subscriber). My argument would be that I'd never click on the ads anyway out of principle, so the ad blocker is just me delegating the ignoring of ads that I would've done myself regardless. Also that if I couldn't turn off ads, I wouldn't have subscribed and they'd make even less revenue.
That said, I doubt these companies would sue because of the risk of setting a precedent in favor of the consumer. Scary legal letters (e.g. cease & desist letters) perhaps. But given enough customers, at least one will have the resources to hire a good lawyer and fight it all the way to court.