As far as I'm aware, if you post information in a place where it will be publicly accessible, then you are tacitly agreeing that third parties will be able to a

As far as I'm aware, if you post information in a place where it will be publicly accessible, then you are tacitly agreeing that third parties will be able to access it and use it as they please. That's not a right that needs to be given to these third parties. It exists from the get-go, and must be explicitly taken away by something like copyright.