I think what GP is saying is that when lending (or for that matter giving away) print books, libraries don't copy anything, they just distribute purchased works

I think what GP is saying is that when lending (or for that matter giving away) print books, libraries don't copy anything, they just distribute purchased works, which they have a fundamental right to do (in the US). That's different from the IA first making a digital copy and then distributing that copy, which there is no fundamental right to do.