The assumption that if we do away with copyright all books would be free is just that, an assumption someone made in this thread. Obviously they'd bring in less money. But when a new book becomes available the publisher, or the author if it's self published, is the only source of that book at first. If people want to read it they'll probably buy it.
Since there isn't any copy protection it won't be long before other people are selling it as well. And of course those who buy it will be able to easily share it with their friends. And the author will only get praise and a lot less money for his work. Is that a terrible thing for a work of love?
I just googled the beginning of copyright and it seems that it began with the Statue of Anne in 1710. Some things written before there was copyright are the works of Shakespeare, Moliere, Christopher Marlowe, Milton, Cervantes, Hobbes, John Donne, Spinoza, John Locke, Pierre Corneille (El Cid), John Ford, John Webster, William, Congreve, Ben Johnson, George Herbert, Francis Bacon, William Wycherley, Ben Johnson, Thomas Middleton, Thomas Browne and Isaac Walton. I left out those whose books were primarily scientific or mathematical such as Newton, Pascal, Galileo, etc.
Just think, if they'd had copyright back then we might have heard of some of them.
Barry