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.