Yeah. I'm willing to spend $50 and more on the right book: the one that covers what I want to learn, walks me through the finer points with good pedagogy, and points me to other places I can learn more when something is outside scope.
And I know the kind of effort involved in creating such a thing is possibly not adequately rewarded at $50 retail -- $10 per retail sale might well be a disaster that leads to a glut of even crummier books.
The problem is that until I invest the time to read it, I don't really know whether it's a $50+ book that delivered what I'm asking for or a $5 book I could have gleaned from basic docs and blog entries but priced as a $50 book.