Hmm. I can't, as a crafter and lover of all things re-purposey, get behind destroying something perfectly usable in such a fashion. I could support using a beat up book with a section of pages missing, or a scratched cover. Or spines from mass market paperbacks that have had the covers stripped for return. This just seems frivolous and wasteful. I don't think I'd object if the books were lined blank journals, though, so maybe my objection has to do with the fact that the books looked perfectly readable.
Not that I haven't bought things with the intention of turning them into something else, I certainly have! Off the top of my head, I bought some wooden cutting boards and football/baseball shaped cutouts from Target's $1 Spot and decorated them to hang on the wall. I've picked up AOL mailers from the stacks at the grocery store to use the discs as a paint palette, ceramic tiles from the local Freecycle group to pretty up with photographs and paint, etc. I've purchased vintage dictionaries and encyclopedias at the UBS and library sales with the intent to "do something with them some day."
So back to my earlier point: This just seems frivolous and wasteful, as is. Maybe she explained in her commentary what she has planned with the stacks of pages and covers? My sound wasn't cooperating.
I have seen some pretty amazing things done with books that didn't cause my inner alarm to go off, for example:
Edinburgh's Mysterious paper sculptures
And I'll leave you with a snap of something I re-purposed, a small wooden (particle board?) box that AOL mailed a CD to me in several years ago that I turned into a tabletop photo frame.