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.
They have psychological issues not behavior ones that prison will serve them for the right purpose. Prison will rather as you mentioned escalate the addiction. They need to be in some rehabilitation center where their addiction is analyzed and they are given treatments along with therapies that could help them in overcoming the bad thoughts they have. They are not criminals rather they shall be treated as mental patients.