He was actually talking about the importance of investing to make money, but in emphasizing this, he talked about gambling houses and betting shops; only being found in Poor neighborhoods, while investment banks, equity firms, asset management firms are only found in rich neighborhoods.
If I were an investment operator, I would put the location of my firm where I likely get a client who had money to invest and that is in areas where the rich reside because the rich are educated that money begets money if I am a gambling operator I will position my betting platform on a place where I can sell dream with their bets and that is on a poor neighborhood because, for a few dollars, they have a chance to double or triple their money, the poor people are ready to take a chance on a few dollars for a chance to win big.