Any idea how they go from your photo to your facebook profile?

Presumably they'd need to scrape facebook for all profile photos and names, which isn't that easy? (I could be wrong here, I'm sure some company would sell you that data) Alternatively they'd need to link your picture to a name, which they could do with a loyalty card, but I don't think that's very likely for cheaters (why would they have a way for the casino to easily track them?)