I would think yes. If they didn't, why would an advertiser spend money with them, knowing full well that part of it was being thrown away on fakes?
It could just as easily be said that it's in Facebook's interest to appear to want to find and delete fake accounts. As long as their customers (advertisers) believe click fraud is being addressed, Facebook wins.
If that were true Google would not have banned fake Adsense clicker. I have experience in FB market and I can tell you that none of us care about Likes. We care about eventual conversion (What % of people called up to know about our product?) which is a very good filter for all fake people.