As far as I know that most of the religion don't take gambling easily most of the case it's been seen that gambling is prohibited and not encouraging. And I think that there is no exact answer or no explanation of your question that why in some religion gambling is forbidden. Gambling is forbidden on there religion because it may on thier religion books. If you do respect all religion then they are was will know explanation. And now your totally up to you what you want to do gambling or not. You come to your options with your opinions.
Don't explain nothing to anyone. It's not others to decides on the activities we should engages, rather its our main job to know If we're ready to take unpon ourselves for the risks upfront. We should create out time to mapped our strategy and know basically what we need. Gambling is prohibited when it comes to most strictly religions, and these activities is consider to be sin and goes against the substandard system. We should always be conversant with the system and knows what we need.
That's means, people needs to responsible with anything he doing, including if he decides to playing gambling even if his religion prohibits gambling. He will choose what he wants to do and must knows what the consequences of what he do so he can thinks what he must choose.
People who playing gambling and knows that gambling is prohibit in his religions will have their opinion and we can't force them to leave gambling. They will decides when they will leave gambling and while they still playing gambling, we can't do anything and only watch they playing gambling. Related to sin because of prohibition on their religion, no one will knows about the sin so that makes those people still playing gambling. But if someone decides to playing gambling, he must be careful and always use limitations.