Nah, I disagree. In my country, there are videos of people from the lower class playing slots while driving or working. When I visited a well-known local online casino, I saw a lot of whales playing, but there were even more people from the low to middle class. Why? Because of poverty. They want to escape poverty through gambling. So even while working or driving, they’re playing slots. It’s their greed for money that pushes them into that situation, and it’s usually the lower class people who end up getting into gambling because of that.
But I would agree with the OP because if you notice, those countries that are leading in spending on gambling are countries that also have economic capacity, those with higher per capita incomes, can also spend more on gambling. And besides, their culture actually supports gambling, which puts them ahead of other countries in gambling.
You are not wrong, poor people gamble more to become rich, but to be honest, there are many poor people in the world who do not know about gambling, meaning they are so poor that they do not even have the opportunity to learn about gambling. And besides, there are classes even in rich countries where many people want to get rich easily by gambling.