Actually gamblers are aware that the house or casino always wins, but basically. Humans have the instinct to seek sensation and excitement by gambling, even though there is a risk of losing money, people still like to gamble even though they know they cannot win because they are fascinated by the great hope of getting a big win.
And winnings or big winnings are real and not fraud, but this is a matter of luck, if you are unlucky you will always experience continuous losses because high expectations make you continue playing without caring that the house always wins.