I would seriously doubt he did anywhere near that amount himself in profit.
This is clearly a loud "warning shot" to all future spammers of Facebook.
Here is some more of the story and what he actually was doing.
Facebook wins $873 million case against spammer
That is obvious, but it does mean that he was spamming to a very high degree, to be sued for that amount. Which means he was making quite a lot of money with so much spam.
Edit: Actually 3-4 million spam isn't that much compared to most elite spammers. He is one unlucky fuck.