I find it implausible that he didn't find a single person who took the gold coin. Odds are he'd find someone who knew the value of gold. What would have happened to his video had the first person taken the gold coin? Would he have bought another one and kept trying? My feeling is that if someone asked for the gold coin, he probably just gave them a little extra cash ... saying something (before the cameras were rolling) that he wouldn't actually give them the gold coin, probably something like, "Hey, you can make a few bucks if you agree to go on camera and answer which one you WOULD take if I were to give it to you."