Following from the scam artists I saw in Paris. Here is one that I saw in Barcelona. Avoid these people at all costs. Watch your possessions too. I was very lucky to get this shot. The next frame was blocked out by one of his cronies who came out of nowhere. You don't know who to trust. You will notice that there are many people (usually another 3, including a woman) betting on this game with this one guy but they're all fakes!
The cronies will pretend to be upset when they loose and then bet big and win, which sucks people in. They also attract bets by pretending to cheat when the dealer is not looking. I will guarantee that you will loose. Even when its a 100% shot, you bet and there's a slight of the hand and you suddenly loose.