Abr1de - ah, I see, so the "man in Whitehall" knows better than parents what is best for their children, does he? How very patronising.
Yes, some parents will not buy books and will prefer different approaches (including ignoring their child's development altogether). But 'twas ever thus and I fail to see how, apart from compulsory reading classes, one can address that.
Besides, those that attend libraries now will also be the ones that will pay to maintain the service - those that don't already attend will be unaffected.
If something is important to you, you will make sacrifices (leisure, hobbies, luxuries etc) for its sake.