I'd push back on your theory that the problem is your biometrics having been abused by a third party (rather than merely being abused by Faceboot...). I'd say the base incentive is that they really don't care about adding new users, so their false positive rate is set way too high. They think you need them more than they need you. And for Faceboot Marketplace they're probably right (about 3-4x the selection of Craigslist IME, and a corresponding difference in interested buyers). I'll still browse and post things on Craigslist, and when I see something for sale on both I'll respond with the Craigslist method to support its mindshare (also straightforward email/SMS is a heck of a lot easier than having to use Faceboot Messenger and then nudge the conversation over to SMS for the actual meetup).