Then I would say the casino owners will cry on this as they keep winning, so they ain't going to get any profit. I don't also agree on the Martingale strategy (well, it can slightly increase your winning percentage, but it's not guaranteed), since even if you have unlimited money and bet, if you sum up all of your losses and cross-check your winnings, it will be still a loss. If there is a 100% winning strategy in gambling, for sure, no casino owners will be building it if they are just giving away free money.