just shows how gambling will always exist anywhere
Yes, gambling is everywhere, even in remote places like prisons. This is especially true for those imprisoned for gambling. In some countries where gambling is illegal, those caught gambling can be imprisoned. I don't think prisons are as strict as we imagine. They can still gamble, even if the stakes are a pack of cigarettes or anything else; even those in prison can do that.
This is because gambling is fun and profitable. It is like an essential already for the human kind. Gambling in prison is not surprising compared to gambling in other places like church or if one has a strict religion, this is because prison as we know it, is a place for the bad guys (I'm sorry if that was harsh).
We can even see it in movies. It shows that it is only true. There are fictional movies but this one is more obvious. I know this is crazy but what if there are also who gamble their life away inside prison? Like if one who loses are going to get killed right away? It is high risk but makes things inside the jail more peaceful because normally killings occurred during a riot.