I have not done anything of this level and I dont think I will ever do such things.These things are made by ill people who have the addiction as their illness.They will do anything to achieve their goals just like a drug addict would.I think that some years in jail would be the right punishment for such persons and also there to be treated for their illness.
I don't think prison can actually help them to reduce the addictions and it will just create it more intensely in them and when they will be out in freedom, they might bet more furiously to make up for the potential wins they imagined they would have made had they not gone in prison.
No contact in gambling would help, to be in prison is a big suffering of anyone who commit a big offense and maybe that would help for him to realize that he have done a big mistake due to gambling addiction. However, being in prison is different compared to being in a rehab that the purpose is to help people with gambling addiction to get out from it, in prison, you just serve in years and it depends on a person if he will change or not.