It is not really greed IMHO, it is more like a click in some people´s brain that lead them to feel a strong stimulus when winning and not much of a pain when they loose. They appreciate two equivalent events differently so earning 50 makes them very happy and loosing 50 does not make them sad. Thus, an advice is to limit your gamble time, for example, gamble 1 hour a day and make sure that you can do so sustainability within your budget.
That still greed because they got a strong stimulus when winning and wanting to make more money than the money they already got before. They do not remember that enough is enough and if they are still trying to make more money, they must know the consequences of gambling. Maybe some of them will not feel much pain but for the others, losing their winning will be a pain in their head but they can not do anything even if they are trying to recover from their losses and chase their winning before.
It is not easy to control our emotions so as not to be greedy, because it is a fun thing when we manage to win gambling and get money.
Even though the victory we get can be lost instantly, if we experience defeat when playing gambling again to be able to get a bigger win.
Therefore, why gambling has an age limit, so that people who play gambling are expected to think maturely. In order to limit ourselves
when it is time to stop playing gambling, if we play too much it is also not the pleasure we get. We will be stressed, because we know
the longer we play gambling, not the more money we make, instead we can lose even more money.