That's what the internet does: it makes things that took days or weeks before (nearly-)instantaneous. If I have 100$, I can lend them to someone (via paypal or whatever), and when I get them back, I can immediately give them out again. I don't have to wait for them to physically go to my place (or a bank) and return cash.

If your whole defense hinges on "borrowing books has to have an inherent delay of X hours/days/weeks before they can be given out again", that's a very weak point in today's day and age. It's like saying "sending mails is bad because it is nearly instantaneous, and you don't have to wait for the postman to deliver your letter".