You could establish contracts with publishers outside of copyright, which is how NDAs work today. It's probably a reasonable thing to do anyway, otherwise there's nothing stopping a publisher from telling everyone the plot summary of your newest novel.
By the same argument, wouldn't all the things you don't like about copyright - like restrictions with what you can do with the thing you have bought - just be put directly into the purchase agreement.
Isn't the way to focus on creating consumer protection rights, rather than just leaving it to people with the best legal department and deepest pockets to control the rules?
From my understanding what's keeping us from this kind of dystopia are restrictions on shrinkwrap agreements, general restrictions on one-sided contracts, and the fact that breach of contract "only" creates civil and not criminal (like copyright) liability.
Good point.