If that is what you are relying on, then Facebook also should not have ban any ICO ad thinking the amount of fund generated from that point. Before you can conclude that the profit from ICO is that amazing, do you have access to their books. It might surprise you that profit from ICO might only contribute just a small percentage of their revenue which they might be willing to let go when decisions gets to that point.

Again, when companies take decisions, not all is based on profit, its sometimes for strategic reasons. If they use Google in China, I am sure that they won't display ICO ads because China has banned it would you now say they would continue displaying it because of the amount of profit they generate? And what would you say about the forum admin that stops selling ad to ICO promoters, you think its only about profit? Another reason would be the trust in the crypto market which is gradually reducing with the amount anomalies going on and for a company seen as supporting that, they are gradually losing their credibility. In all they can do it and nothing will happen.