The "scale" itself is the problem. Because companies are so huge, and their reach is so huge, it invites techniques that increase the efficiency of attacks. Human beings weren't meant to handle things at such scales, and that is part of the reason we have the problem of AI in the first place.
If we lived in smaller, more self-sufficient communities, then we would not have scale and the people in such communities would not have much desire to develop AI either. AI is the natural reaction of a large populace who look for a technological solution to the immense chaos of information.