Because most people in society, across all wealth levels, refuse to live within their means. I was quite disappointed when I discovered this, because I thought that if I made enough money, I'd be able to support all my family. But then I started noticing that the people who were broke generally had newer cars and computers than I did, and that families with multiple six-figure incomes were spending their way into bankruptcy. And the government does it too, accumulating ever more debt.