I know a site that places an adblock (the only one on the page) directly under the header, and above the rest of the content. It's a top site in its area, not mine by the way, goes back long before AdSense, and has tons of unique content. The webmaster implemented that setup to boost income, which it has, after having an adblock in a less conspicuous place for a long time. She has an active and loyal following and has not, apparently, alienated them.
I don't think you can assume "MFA" based only on that kind of placement, particularly on a page that has good, unique content. Aren't sites with no content other than ads and nav. links even worse?