I kind of agree with your point, with the caveat that I just don't want to spend much money if I'm not getting much out of it. I'd happily buy a book for 200 eur if I knew it's going to be worth my time. In the recent years, I've mostly regretted the time I spent on books. Life is short, free time is scarce, and there are so many other things I could be doing.

In this case, I'm definitely curious about the book and would like to skim through it just to satisfy that curiosity, but I have my doubts as to whether I'll get much out of it (I've been writing C for 15 years and I do it professionally). Maybe there are gems of wisdom (or things I've overlooked) in it that would make it worthwhile, but it's possible I'd just regret the time and money spent :-(