If you are a responsible gambler and moreover a professional gambler, why should stop or quit gambling for a month to give the allocated money to them?
Why we don't change our mind to:
I think if you are a professional gambler or if you are not addicted to gambling, leaving gambling for just one month because you want to help shouldn't be a problem.
True, if you are not sincere in helping, it can be considered that those who donated to the poor have lost at the gambling table. I prefer to place myself like them, if I were a poor person I would feel very sad if there was no one to help us. For that reason I prefer to sacrifice my gambling habit to help them. Although helping the poor is not a demand, shouldn't our fellow human beings help each other ?