A pet peeve of mine:

When a new publisher takes over a title, and makes you buy the whole thing again, instead of just updating what's already there. This just happened with the San Francisco Municipal Code, now published by Municode. They're making the library pay $401 for a new edition of the code, and then another $280 at the same time for update service. But our firm can't not have access to the Municipal Code, so we'll pay and watch our library budget hemmorage money. There has been much complaining about this on the local law library boards, but aside from starting a POD print operation and taking over publication ourselves, there's not much we can do.