The thing is that if rich people get money, they're not going to start businesses with that money. Why? Because people start businesses in order to make money. And rich people are already rich. What the fuck they need to produce goods for? They already have money and wealth, right?
No, people create money to make
more money. Bill Gates didn't sell Microsoft after making his first few million. Steve Jobs worked until he was too unhealthy to continue working. Many sell there companies and become venture capitalists, essentially helping start many new businesses. Hell, even Opera, who hasn't produced a single product I like and is one of the richest women in the world, keeps finding more ways to make more money. Her show goes off the air and she creates an entire crappy network, O magazine, etc.
Therein lies my point. The upper crust only invests in an economy so long as the upper crust still desires goods and services and improvement in themselves, thus generating improvement in the lower classes as a side effect. One the upper crust becomes satisfied with what they have, they no longer effect society in a positive way, and therefore should be replaced by some other, hungrier, section of society.
Starting businesses is not the only way to "invest in an economy." The rich constantly want things, just like the middle class and poor does. Many, when they have the money, create more jobs through the luxury spending. Valets, maids, tutors, nannies, personal chefs, landscapers, pool cleaners, carpenters, car detailers, boat cleaners, boat storage, marinas, personal trainers, interior designers, party planners, etc.
Why does this so seldom happen? Because if you're rich, you tend to enact laws that keep you rich and reduce competition. That's why. Bloody bastards.

I agree with this statement. The problem is more because of government than capitalism. What most people think is capitalism is really crony capitalism. No one, including businesses, should get special treatment from the government. Without these laws, it would be much easier for the poor to start and open businesses, giving them a much better chance to rise from poverty. Instead, this system has created a system that makes it too expensive and onerous to start a business unless you are already rich. Not to mention protectionist guilds that protect a job field from competition; requiring law school instead of simply passing the bar, test for flower arrangement in at least one state, certification requirements for interior design, etc.
Here is a great new video from Institute for Justice about licensing requirements.
http://www.ij.org/license-to-work-release-5-8-12All of this is allowed to happen because the government has the ability to allow it.