The status of the physical condition of a book is a legitimate reason to prohibit photocopying. Also, some rare books, meaning rare by the accepted professional librarian standards, may also be excluded from routine user photocopying. The physical act of copying is far harder on bindings than many common users may realize. Opening a book until you hear the "pop" is NOT a good thing despite this too often being done by someone preparing to make photocopies. However, a book that is part of any library collection should otherwise be subject to the fair use exception of the US Copyright laws and thus, available for photocopying as would any other item. Sadly, all workers in libraries are not of the card carrying librarian variety and may not be cognizant of these principals. Your Obedient Servant, D. A. Bass-Frazier (semi-reformed Reference Librarian)