Gambling is for adults, and it is expected that you should know what you're getting yourself involved in before you even start gambling. Games in the casinos been designed for you to lose and for the casino to win, but it still does not mean there are no huge winners every now and then from the same casino.
Sometimes from some of these games, if you believe that you're never going to win, then you will never ever win. But if you believe that yes, it is possible for you to win, then the chances of you winning become higher automatically based on your belief and mindset.
Yes I agree with you that gambling is for adults who should look closely at the terms of the game and see if it favours them before they can play. They should consider their chances of winning if it favours them or not and if they ain't comfortable with what they are seeing, they should walk away as it is not mandatory for them to play the game when it's obvious to them that winning is very unlikely. But I don't think winning gambling is about believe I will rather see it as more of luck than believe. I have seen gamblers who has kept believing that they were going to hit the jackpot someday years ago, and till tomorrow they haven't won any substantial amount from gambling. Is it that their believe is not enough? So how then do we measure the standard of believe that will make a gambler win big?