I don't think gambling addiction is the most dangerous compared to other addictions, as you said gambling addiction will make ruin your financial, that's all. Actually drugs addiction is way more dangerous than gambling addiction since it will ruin your financial and your health condition. If you lost all your money but you still have a good health and body, you can get a job. But when you don't have any money and you're sick due to drugs, it's almost difficult to get a job to make you survive.