FuppingEll, I wasn't asking the question of mnhq. I was just asking the question.
And when I spoke of 'some button' that alerts browsers the the fact that a page is an advert, I wasn't imagining that MNHQ would do that simply as a service to users. I was (and am) genuinely ignorant as to whether the legal obligation for advertisers to make it plain that a piece of content is a paid-for promotion could be satisfied with words only, or whether it required something to be built into the coding of a page so that it could be recognised as an ad at a technical level.
I can entirely underatand how frustrating ad blockers are for MN, but it is just absurd to treat the vulnerabilities of a free-to-access business model in terms of the quasi-moral concept of free-riding. If someone handed me a freesheet at a railway station and I folded the page so that I could comfortably focus just on the news story that interested me, would I be at fault?
Additionally, the very common experience of encountering a requirement to disable an ad blocker in order to access a particular site makes it completely reasonable to imagine that MN have (thus far) taken a business decision to continue to allow the use of ad blockers (for whatever reason I don't know), so that makes it entirely reasonable to access the site on that basis.
If they make a change in that respect, fair enough, I will be off (unless they make their ads less intensely obstructive)