i posted on the public internet with the intent and understanding that it would be crawled by systems for all kinds of things. if i dont want content to be grabbed i dont publish it publicly
you can't easily have it both ways imo. even with systems that do strong pki if you want the world in general to see it you are giving up a certain amount of control over how the content gets used.
law does not really matter here as much as people would like to try to apply it, this is simply how public content will be used. Go post in a garden if you don't want to get scrapped, just remember the corollary is your reach, your voice is limited to the walls of that garden.