Well, as a religious leader, there are some reasons he will give that can justify the fact that his gambling attitude is good. If truly he is winning and using the money to do good, then that's a good attitude of his, and it could also be true that indeed God is really showing him the games to bet on. 

I will not judge his gambling attitude because he is not compulsive, according to the story, and he is also using the money he wins to do good to his members. My only fear in this kind of situation is that what if his members decide to follow in his footsteps? There are some members who will want to be like their leader, and in the process, they can become addicted gamblers. That's my fear.

Lastly, I know it's nothing new for casinos to ban any customer that they see as a barrier to their business. Casino is the business of another person, and the casino owner is always praying to make a profit all day, and their profit comes from the losses of gamblers. They always wish for gamblers to continue losing, and if a gambler is always winning, the casino owner will find every reason to block the account.