If they think about family then they will not gamble even though they lose all their money
Do you really think so?
You feel those gamblers out there are okay with the life they are leaving and the life of their family yet they go into gambling?? No, it's the wrong thing to think. I have seen a lot of devastated and depressed people out there whose only hope of living a good life lies in gambling. This people becomes obsessed with gambling due to their obsession with the thought of changing their stories and that of their families to better. In most gambling cases, people feel it's a selfish ambition that causes addiction but I believe it to be depression. Help those people a little of their needs and you will see them stay away from gambling.
The people who are devastated and depressed are only because of gambling, it isn't like they were already depressed and devastated and then they started gambling. And, what kind of needs are you talking about fulfilling? If they spare the money that they spent on their gambling addiction can also be used to fulfill the daily needs of their family.
A person who knows that they don't have so much money shouldn't gamble in the first place. You can't gamble with the money that you can't afford to lose, so it isn't a wise thing to gamble the money that you need and leave your family to starve.