he's not obstructing content with ads, he's stealing ad clicks.
here's what he's doing. those links that he's occluding with the ads are the navigation links for the site; the most frequently clicked links on any site. The ads load last (in fact, there seems to be an intentional load delay), so that you can see the nav links, but as you go to click on them, and ad show suddenly pops up on top of them. next thing you know, your legitimate click to move about the site turns into an unintentional click for an ad for dodge pickup trucks. every one of those ad clicks are money in his pocket. covering navigation links with ads is cheesy anyway, but the delay just makes the whole thing look intentionally dishonest.
this scam is virtually impossible to avoid on mobile devices, which is probably the majority of his traffic. the combination of the imprecision of the touch screen and the more narrow 4g bandwidth makes his entire site one big factory for illegitimate ad clicks.
the giveaway is that the ads would easily fit between his logo and the right edge, but he's intentionally occluding his nav links. what he's doing is pretty brazen. his ad publisher would frown on this practice if they were aware of it.