Yes, people tend to blame others for their mistakes and failures. That's just the way their brains work. More precisely, they are not smart enough to understand their mistakes and accept them properly. This is a poorly developed intellect. There's nothing you can do about it. You just have to pass by if you encounter such characters in your life. I know a few of these people. I've come to the conclusion that it's better not to have any contact with them at all.
I think this happens because they think they will easily win at gambling, and the reason they do this is because they are in an unstable emotional state, so they spontaneously blame other people or the casino when they experience losses in gambling. What you said is true, perhaps it is better to avoid dealing with people like this because they usually tend to always do things that are high risk for themselves, such as borrowing money from us without certainty of repayment because we know the chances of an addicted person returning the money or paying off their debt are very small because they are more concerned with the desire to gamble.