The last couple of O'Reilly books I purchased from Amazon were of poor quality. The content was fine but the physical item was shocking. They were probably print-on-demand books made on the cheap. But the retail price was what you'd expect from a high end tech publisher. I should have returned them. The books look like they were printed on a consumer grade inkjet.
I had heard that the books purchased directly from O'Reilly didn't have this problem. They've even taken away that option now.
Looking back, this had to be expected. The writing was on the wall when they switched from a lay-flat binding for most or their titles to the cheaper, much hard to read while coding, perfect binding.
Yes, they're print-on-demand books, printed by Lightning Source (the last time I checked). They're not cheap to print, at least not at the list price; I don't know what deal O'Reilly might have. However, they're vastly more convenient because Lightning Source will ship them directly to retailers so publishers don't need warehouses. If I'd have to guess, I'd say that O'Reilly might be printing a small initial batch for each book, switching to exclusively POD once the run has depleted.
Source: I also use Lightning Source for my tiny publishing operation. Yes, the quality is not the same as the traditionally printed books, although personally I don't think they're that bad (those I've seen, anyway). In my case, as a small publisher, I would never be able to afford to operate warehouses profitably, because we only have a couple of books. We actually tried, but it was too expensive and time consuming at low volumes. We also stopped selling paperbacks, because it's very difficult to complete on the shipping costs with the likes of Amazon.
I'm surprised to hear that the print-on-demand books aren't cheap. I know you're getting flexibility with print-on-demand, which has value, but if the quality is so much worse than traditionally printed books (in my experience)... is it really worth it for a publisher the size of O'Reilly? I guess that's a question only they can answer.
If people want to buy print-on-demand books, that's fine. It's just not for me, I'd like the option of paying more for a standard of quality I find acceptable. Not enough people are willing to do the same, sadly.
My "JavaScript Definitive Guide" ordered from Amazon.de (and printed by Lightning Source UK, if I recall correctly) was of shocking quality too. I returned it and got a more expensive copy from my local bookstore, printed by Lightning Source International. Very sharp type.
That's generally a big problem with print-on-demand: they literally print one copy at a time, so you have to rely on the printer to do quality control well. Even if you're checking regularly (as we did in the early days), you can never know if the next copy they print will be bad in some way. Not to mention that they also have multiple facilities, so you'd have to place orders all over the world.
There's also a separate problem of pirated printed books, which are of very poor quality.
I have very mixed experience with print-on-demand too. Bought a Microsoft Press book that turned out to be printed on demand... the print quality is bad (looks like a printer set to thrifty "save toner" mode). Together with their choice of a rather anemic font for the text, it's just not nice to read at all. The bad legibility really impacts the joy of reading it.
The Kindle mobi books have issues too. For whatever reason, Amazon thinks it's acceptable to sell mobi books where the code samples are barely legible on a Kindle paperwhite.
I've had this issue with some O'Reilly and Manning titles ported purchased from Amazon in Mobi format.