Final answer:
Casinos use facial recognition technology to spot card counters, individuals who use a strategy to gain an advantage in card games like blackjack.
Step-by-step explanation:
The alliterative gamblers that casinos used facial recognition technology to spot are Card Counters. Card counting is a strategy used in some card games, particularly blackjack, to determine whether the next hand is likely to give a probable advantage to the player or the dealer.
Facial recognition technology can help casinos identify individuals who are using this technique to gain an advantage. By recognizing their faces, the casino can take appropriate action to prevent card counting and maintain the fairness of the game.