Who would buy those ads? That seems to be Facebook's problem.
The 'platform' seems to be dominated by idle people who prefer free services that let them spend their day throwing virtual sheep at each other. That's not a particularly valuable demographic for businesses seeking to advertise their wares.
Much better, by far, to purchase targeted advertising on Google.
There is millions of dollar being made every day with Facebook ads. You can target them very specifically and drive large amounts of traffic cheaply.
No, it is certainly not Adwords. For some offers it doesn't work. For some it works better than search. Just because it's not search does not mean it's not an incredibly valuable marketing channel.
They will never be as profitable as Google because the CTR of the ads is pathetically low (compared to search) and the clicks are much less valuable, but there is massive traffic there. Even if they never develop the killer ad product there is still a big business there.
I guess the side would not last long with this approach, but it would make a few dollars in the next days.