Rather than merely stating "this is for adults," why not address the decisions they are making, the possible results, good and negative? Its not just about keeping them away from gambling, its about teaching them to make smart decisions, period.
Children that can think for themselves rather than merely follow the crowd are what we need to produce. We construct a better future this way.
guiding children to be independent is something that all parents definitely want and of course parents hope that their children can be independent as a whole, when they are still small it doesn't mean they have to be independent, teaching must still be done, because when the teaching that is done is successful in applying, the child when he is an adult may be able to think well not to be reckless in making decisions. sometimes I see a video that shows the sentence "the parents succeeded in educating their children well" I think they have done this since they were small by educating them well.
Independence is It's not about tossing them into the deep end and screaming, "Swim! Show them the strokes; then, let them paddle on their own. Not a drop-off; this is a dance. See them, change, let go somewhat more every time
This is survival, not only about freedom. The planet is a strange place with lots of unknowns and inconsistencies. Give your children the tools to negotiate that turbulence; they will emerge from it stronger on the other side.