It would be difficult to manage the quality. That's OK if the price reflects the quality, but if I'm to spend €100 (say) on a large photo book like this I don't want thin paper, imprecise binding, or other corners cut.
It's likely that you have a weird situation where making ten books costs about the same as making a thousand, because ten would have to be done via quite expensive printers and a bunch of hand setting, but a thousand is done via complex machines that once setup, are relatively cheap to run.
As an aside, print-on-demand from Amazon and others has been pretty amazing for black and white text, if you quality check it, but it quickly goes sideways for hardback color books.
People have even reported bad printing on simple text, but it's not clear if that's bad files (as the user, you have quite the leeway in what you send them).
Indeed, you'd have to have very clear specifications and perhaps sample prints that can be ordered to get samples of various qualities available; and then public review/rating system would be necessary for people to build up cred.
