Does nobody else see a possible conflict of interest and ulterior motive here?
Yep. But it's more interesting because of that. Generally speaking, people feel comfortable if they are with groups who behave as they do (so I understand). If that's the case, the publishers could be doing themselves a disservice with this!

"57% of new books are not read to completion" - I've never measured it, but this could be true of my books. On the other hand, my library is heavily biased towards dictionaries, encyclopedia, concordances, and other reference books that are not things one sits down and reads through. But as a slightly amusing example, a Christmas or two ago I was was given "The Road to Reality" by Roger Penrose which claims it appeared on "The Sunday Times Top Ten Bestseller" list. If there are more than 100 people in the UK outside of Universities who have read it cover to cover I'd be astonished. Opening it at random, I see:
The Dirac equation can then be written as an equation coupling these two 2-spinors, each acting as a kind of 'source' for the other, with a coupling constant 2^-1/2M describing the strength of the 'interaction' between the two.

There then follows an equation the complexity of which is beyond my HTML skills and involves nablas and other characters for which I don't think there is a html equivalent.

So I wonder how (and why) did this get onto a top ten bestsellers list?   Stephen Hawking jokes in "A brief history of time" that he had been told that each equation he put in a book would halve the number of purchasers. Starting with some 6 billion people, it takes a mere 24 equations to be less than one person - or by the end of chapter 2 of the 34 chapter Penrose book. (Of course, those were the lighter chapters)