It's called "trading up addictions". When I got sober in 1991 I turned to obsessive shopping, later food. He's hiding his actions from you so he knows he's doing something wrong, that gambling has brought conflict into your relationship. There's no difference in hiding bottles or hiding evidence of gambling. Whatever he does, you have no power over his actions. So perhaps it's time to take stock and ask yourself if this is what you want in a relationship?