It's like they won't want to work and yet gambling isn't helping either, I guess this effect happened because they have tasted how it feel like to win some money through gambling so they shut every other doors.
Did they tell you that they wanted to stop gambling or you are trying to help them stop gambling by providing them with something to occupy their time. I don't see it as laziness because they don't have the passion for what you introduce them to. Those guys might be addicts unknown to you. It's difficult for an addict to stop gambling when it's not of his own will.