[Google234]

If the library owned an effectively infinite copies of each book why wouldn’t they let you borrow one copy of each book?

[chongli]

The online library known as archive.org tried exactly this. They got sued, to no one’s surprise.

[gfedtbyby]

Because authors and publishers wouldn't be very excited about that and would lobby governments to limit that (and I 100% believe they would be right to do that).