Hisah you are such a pessimist, show me one company that has I billion faithful clients, just one. Lukewarm profits yes, but when they institute buying stuff directly through FB , technically to get $1 billion in sales, all they have to do is get everyone to buy something worth $1. Ofcourse there are people who wont buy, but there are people who will spend way more than a dollar, compute those numbers, get the mean, standard deviation, expected values and voila. FB makes economic sense, but only if the model works. Get the users hooked on FB market/commerce, and the profits will flood in.