Being a responsible gambler is not easy, it's easier said than done as they say. If I say being responsible is easy and everyone should become responsible, it's because I have control over my emotions and I feel that anyone can have that but in reality, it's not as simple as we might think it is based on our own thinking.
Responsibility here may be more about the use of money either going in or out of gambling. So if someone can be responsible for losing from gambling, they will probably think more clearly and not be careless when placing bets in casinos or other forms of gambling.