I think you and redwood are violently in agreement. If you have more money, you can save your money and that money will make you more money. If you have less money, you can't.
I agree with the statement, but I disagree that it's responsible for the income and wealth disparity beween the rich and poor. Yes, money will make you more money, but by definition that increases your income.
Upvoted for "violently in agreement" — I'll have to steal that one