It seems to me that in countries with lower living standards, gambling is more widespread strange as that may sound. People believe in even the slightest chance of getting rich. Similarly, in countries at war, I know for sure that soldiers often gamble to relieve extreme stress, and this can lead to serious consequences, since many of them suffer from severely damaged mental health.
Casinos are certainly looking at the profitable markets to tap into. It may be true that the casino business strategy in countries with a low standard of living will be profitable for casinos. Because with simple strategies and basic promotions, offering bonuses and large win possibilities will be very appealing to people in such countries. That is one of the factors, and another factor may be related to government regulations that support gambling when well-managed.