Just what can be done to ensure limited exposure of this kind?
instead of limiting exposure, why not educate them about it? I mean, educating them about gambling and the risks and what it can do to people, is one of the best ways to let them know that gambling can be dangerous and there can be grave consequences when it is abused. I have been mentioning it a lot on this forum whenever a topic like this pops up that "gambling awareness" should be added as a curriculum in schools or at least a subject about addiction in general.
I think it would definitely have a good effect on many teenagers and would definitely save many from addictions. Of course, this does not guarantee that in adulthood they will not want to try to start gambling and lose all their savings. But I think at least half will understand why and what gambling is needed for. It is for relaxation with the allocation of a small part of the money for this that we can afford to spend irrevocably, for the game, and not a bottomless pit into which everyone throws money to the last with thoughts, either I will become a king, or become a beggar. Extremes are always bad, you need to maintain a balance in everything.