There is something really scary about this being all secret functionality. How do I know my scanner/printer/camera/... isn't snitching on me when connected to the internet?

Also can I put those dots in any picture/document to mess with cameras/editing software? Or is there more than those few dots to it? Would be kinda useful for public images, to at least annoy some stalkers, impersonators and other creeps. Doing this all over the place could also really support open source projects like GIMP!