Gambling isn't the solution to poverty it will possibly drown you deep into more poverty.
It is not only people who are trying to beat poverty that gamble, many rich people still gamble but show these character of violence, aggression and anger. So it cannot just be gambling alone, but can also be linked with financial insecurity. Some people easily get angry, violent or aggressive near the point where they do not have enough money for expenditures. This is why people who gamble and loose money start feeling insecure financially because they are loosing money, so they become easily angry, violent or aggressive.
Gambling isn't the sole reason why people become aggressive, anxious, and depressed. Sometimes it manifests because they have tons of problems to begin with, such as having financial difficulty and despite that, they still gamble anyways because they feel that gamble can be some sort of diversion of attention, without noticing it's also starting to consume them. It even becomes the main problem to some because addiction slowly creeps in the moment the person disregards practicing responsible and moderate gambling routine. But we can't really judge them can we?
It's best to criticize and be a concern citizen once in a while. Although just make sure to not meddle on someone else's business. There's still a fine line between being concerned and just being plain rude who loves to pry.
And in my opinion, people who are in a phase of economic difficulty and then bet on gambling, of course, this is not a good and correct solution but this is the beginning of him getting worse in the future, with the beginning of gambling and succeeding in getting a win, of course there will be thoughts of returning to gambling even with a larger nominal to get a bigger win too, but without them realizing it is the beginning of them entering misery because gambling is not always profitable.
It is indeed difficult to stop gambling addiction but we must remind each other not to fall deeper before the addiction continues until who knows when it will achieve a sense of satisfaction from winning. It is true that you should criticize occasionally even if it is not to interfere in his life problems even though it will cause conflict.