That would be the hardest part especially for those who are addicted to gambling. But if you are not addicted, if you can control yourself or if you don't even have to control yourself because you cool with stopping at any time, then gambling is like any other recreational activity.
Actually family support is important things if you can to get rid of gambler addiction.
My neighbour decide to suicide since nobody even their family take care about him ( he was being chased by debt collector )
If your family keep on supporting addict people I dont think they can be mature enough to think and stop on gambling moreover if they get loan and gambling again just to recover their loss, that is really bad thing to do. Gambling actually is never wrong, it is just wrong if you cant control yourselves. If you can control it you wont become like this though