Google's advertising business is built on trust. The moment there are a few scandals involving fake/robot ad clicks, big advertisers will remove their ad campaigns.
Google is the only organization with the data to show this happening at scale and they don’t have incentive to connect all the one-off anecdotes.
So while it is risky, not sure how they could be caught. I don’t think they are running click fraud bots, but it’s hard to quantify how hard they work to stop them.
A friend of mine estimated that 1/3 of ad spend is click fraud but it’s just in the wash because it’s hard to stop.
Google's advertising business is built on trust. The moment there are a few scandals involving fake/robot ad clicks, big advertisers will remove their ad campaigns.