Religion is nothing but a bunch of principles and faith. You may claim that you have no religion but you cannot say that you do not have some principles or rules in your life. All those rules that keep us safe make our religions and we follow them. That's all. Some people may not play gambling because they think it is harmful and it is while some religions prohibit it and safe the person beforehand, without trying.
Im sure atleast everyone has religion. Even when they claim that they are atheist, they know that it is wrong to gamble but we still gamble right ? we dont follow the rules and we keep gambling, when we are addicted then it is going to be hard for us to get out of it. We keep on not wanting to quit until we realize that it is too late to quit
Everyone knows that despite of difference in religions, it is a common thought among all of us that gambling is not good at all. It could not be classified as a virtue but is more a sin. Gamblers being aware of this fact do not give up on it just because they are addicted to it. This is not easy to eradicate form your daily routines and need a lot of time and thinking to quit.