<...> but "Or you go broke; not having money to stake will make you to never go back". that would do and even change the mindset of some gamblers, I think.
Depends. There are some that even when they go broke they get to borrow. If the bank won't lend them from some dangerous private lender they will collect the money back with aggressive methods. And some even go as far as stealing from their relatives to keep gambling.
The one who has a serious problem has to do a psychological exercise of willpower to quit, probably with help.