Multicopy purchases are common. The Baltimore County system recently ordered 1500 copies of a Danielle Steele novel before publication. Even small libraries buy several copies of high-circulation titles and then may but two or more of a reference work such as a tax guide. One can then be anchored in the reference department while the others are circulated to the public. Purchases by libraries undercut store and direct mail sales.
Experience shows just the opposite.
Getting exposure through libraries can create demand in bookstores and increase direct ordering from the publisher. Some thrifty buyers want to try out the product before buying it themselves. Librarians have good memories for imprints, unlike most general consumers. A publisher advertising regularly in the library media and trade publications wins not only recognition but also respect and credibility. Over time this translates into extra sales, as well as stimulating near-term revenue from specific titles featured in the ads.