Does she use a browser to access them, or the Newsstand?
The Newsstand applications for both of those publications seem remarkably un-terrible, compared to their mobile websites. I agree that many news websites, even the mainstream ones, seem full of booby traps, and that it is a problem in general — just that there does seem to be a solution for this specific case.
Testing it out, I can't find any ads in the New Yorker app. However, the New York Times app has ads on the side near the bottom of articles, and most annoying, inline links to related NYT articles.
The problem with the links to previous articles is that clicking on them (accidentally or not) takes you to the NYT website. Suddenly you start getting the regular annoyances without it being obvious what you did wrong, and you are not automatically logged in so you will also begin getting notifications about using up your allowed number of free articles.
The Newsstand applications for both of those publications seem remarkably un-terrible, compared to their mobile websites. I agree that many news websites, even the mainstream ones, seem full of booby traps, and that it is a problem in general — just that there does seem to be a solution for this specific case.