Yeah half of the problem is that, the other half being some people just have more resources to become more successful... Its not the only contributing factor but its one of the things that defines a difference between those with a few thousand and those with a few ten-hundred thousand (at least where wages are pretty high) ...
Of course I was only speaking figuratively, an economy where everyone is a millionaire is impossible as long as we have finite resources, and of course good money management is only a part of becoming richer, but everyone would have benefited if they were smarter with their money, people would be less poor for sure.