Mathematicians tell us if you play blackjack with "perfect strategy", as shown Basic Perfect BlackJack Strategy, blackjack has a probability close to 52-48, say 52% for the house, 48% for the player.
Now if you go to luckynugget.com, purchase $100 bets, they will credit you $110 as promotion. They require to bet at least $400 before cashing out. So, if you play with small hands, like $20 per round, in theory, you would lose $400*(52%-48%)=$16. There's $100 (purchase) + $110 (free bet) - $16(loss)= $194. Your profit is about $94.
Now if you go to luckynugget.com, purchase $100 bets, they will credit you $110 as promotion. They require to bet at least $400 before cashing out. So, if you play with small hands, like $20 per round, in theory, you would lose $400*(52%-48%)=$16. There's $100 (purchase) + $110 (free bet) - $16(loss)= $194. Your profit is about $94.