Not just education alone, we need to sit them down once in a while and advise them of life's activity be it good or bad, we must let them know what it is. Because If such children finds out about gambling on their own when they haven't reached the required age for gambling, they'll definitely keep it away from you. And doing that is dangerous because it might lead to addiction at a tender age. So there are time were we must show fatherly love by bringing them closers to ourselves and make them trust us by giving them concrete advise in a soft tune and mood, for better understanding.
What you said is correct, it is very important for us to be able to advise our children if they dare to take money without telling them first and they use the money they take for gambling, of course this is not very good and we must advise them well and don't let them not listen and they end up repeating the mistake again, I am sure that if we can give good advice the child will be able to understand it and will not repeat the mistake they have made.
They are just children, or minors, and they aren't matured enough. If they make mistakes like stealing, then maybe we should also reflect a bit if we do our job as parents to guide them, because children will not steal if they know in the first place that stealing is bad and they'll be punish. It's very challenging nowadays since children can get information online, can talk to people they don't know online, and sometimes we can't see everything they are doing.
The approach here should be gentle, we sohuld discipline them by educating them, and tell them that gambling is onyl for 18+ years old.