you probably should not have an rc about not accepting library books. I think a big percentage of hardback books that I request turn out to be xlibrary.

I get lots of HC (fiction and non-fiction in history and medical genres)  and almost none are ex-library books.  Just recently I have decided not to WL HC books so as to pay less when I mail them out after I've read them. 

If the people have the RC "no ex-library books", as I have, they can turn off that RC before accepting the offer, if it's something they really want to read, as I do.  If I'm just interested in reading the book and sending it back out, I'll turn off my RCs; if I'm planning on keeping the book, the RCs remain.  I just assume that's how most people do it.

I post quite a few HB books and right now have 31 that are not ex-library and 14 that are, posted, so my ratio is 2/1 against them being ex-library books.  Pat

I post quite a few HB books and right now have 31 that are not ex-library and 14 that are, posted, so my ratio is 2/1 against them being ex-library books.  Pat

In my experience, it totally has to be with the genre and popularity of the hardback book whether it will be ex-library or not. I request a lot of British books that are never released in this country and were only available in hardback. In my case, a lot of those books end up being ex-library books from libraries in England which ended up in the resale market, thus making their way to the US.