Gambling can't be a reliable means of earning, we may only try our luck in it in a fun-filled mood and not a means that we will base our living and that of our dependents.
In fact sometimes the simplest thing is the best solution, if we make our children see that gambling represents fun and money, but that it is a dangerous activity and that for that reason it is required that the people who do it are of legal age that can represent that they are responsible for managing their money and probably in a casino the money they put in can be lost, it is a simple solution, there is no need to complicate everything, if they are made to see that it is like that, even when they are 18 years old or of legal age they will avoid these things because it is a way to lose easy money.