Community integration is absolutely the way forward, I don't disagree. Ultimately that is NLC's grand plan with ambitious (expensive) town hubs being built across the authority. I quite often get books for pupils from public libraries and it breaks my heart to see the selection they have that is woefully underused, meanwhile I am replacing books with second hand copies from the community library in Tesco.
However, that isn't happening any time soon. In addition, school libraries are so much more than just a place to take out books and it is all the other things provided by a trained librarian that can't really be measured on a balanced sheet.