Because the app has been out since 2008, gone through multiple iterations, currently holds a 2-star rating on the App Store, and still hasn't managed to monetize 60% of their impressions.
So what you mean to say is, we have here a company whose traffic has been bleeding off their monetized, desktop platform into the unmonetized, mobile platform that has existed for four years, and they still haven't done anything about it?
Are we still talking about FB? I swear this sounds more like RIM.