Gambling on the other hand has nothing to do with your physical health (your mental health is another story) and thats why there isnt any entity to keep you in line other than the government and the government always ban the stuff which cant have it under control.
I don't totally agree with this. Gambling directly affects your mental health too. Do you know why people become a gambling addicts? This is because they play too much gambling that their mind fails to recognize how much gambling is good or bad for them. They are unable to make the right decisions and this is directly linked to mental health.
Also if people start to lose in gambling, they will become tense. They will have a very adverse and bad effect on their mind. Just like winning in gambling and getting a lot of money can have a good effect on the mind, losing money will have a bad effect on the mind.