precisely they play gambling just to get money quickly, they are indeed aware of the risks that will be faced from gambling itself. many of them suffer losses from gambling which causes poverty but even so if we often do gambling, of course, naturally addiction in gambling is difficult to avoid
You said it already, they are aware of the risks they are taking, that means they can take the risk.
It is true that gamblers usually don't care about the losses they have, about the time they are wasting in a gambling site or a casino, but I don't think that is a problem if you can afford to gamble. Addiction is still probable to happen but as you said, they know the risks and that means they are aware of what they can lose or what might happen to them so let them be.