They do that (or used to at least). Each book has a single scanned copy that only a singe person can have "checked out" at any given time. There's a waiting line you sign up for.
That's how they used to do it, but is that still the case after they introduced the emergency library? I thought they now lend unlimited copies of the book unless the authors opt-out, and imo it's a little bit legally shaky for them to simply go against the law unless you ask them not to?
