We don't need to market to libraries because they don't order from the publisher and their wholesalers supply all their needs. Wholesalers offer a valuable resource for libraries with one-stop shopping, discounts, recommended lists, standing order tracking, cataloging, and more but they cannot create a need for your title in the library. Of all the people I know, librarians are the least likely to throw away information. Catalogs are information.
Catalogs tell the librarian what's newly published.
What information is currently available to their patrons. Librarians not only don't throw away catalogs, they circulate them to other librarians, file them for reference, and refer to them for up to three years after the catalog is mailed. Librarians are serious buyers. Nothing could be further than the truth. Librarians are consumers just like everyone else.