Of all the activities that are often associated with compulsion issues, gambling should be one with the lowest rates of addiction, and this is most likely the case because people deep down can control themselves very well when they gamble.
Now a person may lose control once or twice, but they will learn from those experiences and never make this mistake again, after all if the percentage of people which were addicted or on their way to become addicted to gambling was really 80% then we can be sure gambling will be banned by now as it would be impossible to have a working society otherwise.
You know, when talking about addiction to hard drugs, it's like something that is demonic (although it's not) because it can derail someone mentally, emotionally, and health-wise. It can just turn someone's better lifestyle into nothing, and that's why it's greatly kicked against, because if it's allowed, society will be full of mentally ill people. Speaking of gambling addiction, it doesn't also mean that there are no compulsive gamblers who are really, really terrible, but since gambling is for fun, it cannot just be ban easily because it's believed not to be destroying their lives gamblers like hard drugs. But the thing is that every addiction has its effects and impacts.