Well, in my opinion, I think that the reason why they cannot stop these crypto advertisements is either because it is beyond their capabilities to control the people using google and facebook(which I highly doubt) or because they are a part of something big or somewhat a hidden agenda that may be hidden to the public. But whatever the case is, we are powerless about the issue. So what I do is just ignore things that are out of my hands and just try to adapt to what new things happen every day as hard as I can.