I've done my share of affiliate marketing in various channels, and Facebook was by far the least successful for me. The guy in this piece doesn't seem to be targeting based on fans of that supplement, or something very targeted. He'd be lucky to get a 1% conversion rate. If I was a betting man, I'd wager it wasn't successful at all. He'd have better luck targeting keywords in Adwords, and preventing those ads from being seen in the city the supplement makers are based at, or something sneaky.