We currently don't require that customers using the People's Network computers are members of the library, though we would like them to join and gain the many benefits therefrom. Our reference librarians can make people members of the library as they do so once in a while so that they can issue one or other obscenely-expensive reference book to People In The Know. (Yes, these are the reference librarians who hide the newspapers under the enquiry desk so that customers can't steal them).
T.Aldous bumped into a couple struggling to get a pram and two babies up the stairs to the library because they wanted to use a computer to check their emails. He guided them to the lift, made sure it was going up to the reference library and told them to ask for a computer at the enquiry desk.
A few minutes later, he was passing the lift and the family was coming out. He was, naturally, a bit surprised and asked if all the computers were busy.
No. They'd been told that they "needed to go downstairs to join the library" before they could use a computer.
To his immense credit, T.Aldous took them back up to the library, got them onto a PC and gave them a membership form, a new user pack and a lot of spin about the services in our libraries.
I can't help thinking that a hard core of our staff wouldn't be happy unless customers weren't allowed on the computers or borrow books at all, just so that they could make sure that we could guarantee to be able to meet demand should it arise (but obviously not guarantee to actually meet it).