Both. I think they are just buying whatever they can get their hands on most of it is going to be junk, but one in a million is going to be a rare and valuable book which we didn’t even know existed.

After scanning and destroying 10 million books, AI companies will have destroyed 10 such books.

(I am obviously assuming a Poisson distribution here where I pulled the parameter p = 1/1000000 out of thin air; point is p is non-zero; and at this scale the undesirable event is bound to happen a bunch of times).