libraries as prime places to steal books for resale

At my library we have been considering raising the limit on the number of DVDs/videos a patron may check out at once. Currently the limit is four. There is no book limit. One of the reasons we were concerned about raising the limit is that DVDs in particular have such a high resale value on the Internet. I saw this article about a library employee who has systematically been reselling DVDs, books and other library items over the Internet for six months and using his access to the library computer to mark them as “checked in” He was turned in because he sold a book to a college president in Illinois who was suspicious about some of the library markings. This sort of thing happens all over, even in sleepy little neighborhoods like mine. Slashdot discusses. What do we do about this? [thanks john]