Thee are many gambling stories out there, some good , some sad yet we still make new addicts every day. I don't think the sad stories alone will get future addicts to stop but rather the society must offer hope such that if I know I can earn say 50$ by washing plates for 48 hours I will rather make my 50$ that way and not through gambling.
In washing plates you are sure you will be getting 50$ but in gambling either you can make the same amount or lose out completely depending upon the luck and the game which you will bet on. People who have excess and lose out is fine but for needy it is quite bad.
We will make money through gambling only when we have enough luck, as you can see sometimes we may make higher amounts in order to start continuously gambling. Once they are making money they will start addicting to it.