If all the internet was is static content, that wouldn't be much of a problem. But we live in world where packets coming to your service result in significant state changes to your database (such as user generated content).
I suspect that we are currently in the valley of do-something-about-it on the graph which is why you see all this angst from the big players. Would Google really care if automated programs were so good that they were approximating real humans to such an extent that absolutely no one can tell? I suspect they would not only be happy with such a state of affairs, they would join in.