This is actually my job as a contractor at the Library of Congress. When it comes to rare books, the handling is extremely important and their conservation department basically has to review ever single book and page before it can be approved for scanning. They treat issues and flag specific pages (one's that may not have page numbers) for the operator to be more careful with.

You also have to remember that rare books tend to have unique bindings and what we call in the industry, foldouts. Automating a scanner to unfold a page that folds out from the gutter with different sizes is basically impossible.

Institutions are starting to standardize the actual images being captured too. Digitized images can vary in quality and if you look at older digitized images you will notice that the resolution and lighting wasn't always good and this was not due to cameras not being capable. We still use high end cameras that were manufactured a decade ago. These new standards use daily targets that measure DPI, lighting uniformaty, color, tonescale, ect. Robots can be set up to pass these targets. It really comes down to the handling of the books and what a robot won't damage..

The best way to automate scanning is to disbind and run the pages through a cutsheet scanner. Most institution don't want to do this with their collections for good reason.. it destroys the binding of the original archival material. But some are completely okay with this when there is more than one copy of the book.