There might still be a chance for these blamer gambler to change, most especially if we talk about their problem and suggest them things that they can do about it. They need a help, so we should not avoid them even though it can be hard for us at first, if we are not used to being blamed.
If they still blame other people, they should immediately stop gambling. They will indirectly trigger arguments with other people. If they meet someone with a tough temper, they will immediately fight because that person doesn't want to be blamed for someone else's defeat.
That's why if we see people gambling, we don't need to get too close to them. We don't know what will happen next, so we have to look at the situation first to avoid any trouble.