Thank you for your comment. Taking routine, mundane tasks away from skilled staff frees them up to deal with more complex enquiries. Lots of businesses now have a self service element to manage queues and make staff available for the more in depth, skilled and difficult to solve questions from students. It started with atms in banks and now even supermarkets have self check outs.
At Polhill particularly it means you can return your loan items at any time. You are not tied to library opening times.
Library staff do not not need to be stamping books, the value of skilled staff is in dealing with specific problems and guiding early stages of academic research.