I think you drew too much of a conclusion of what Open Source is. And, it appears that many of the people who replied have similar ideas.
There is an idea that Open Source software is written by a bunch of software hippies who are anti-capitalistic and would believe in free love if they could ever figure out how to get close enough to a girl. Open Source is merely a philosophy that you can benefit by opening up your software to all coders.
Some Open Source projects are very large, need lots of hardware and actually pay people to do such things as documentation, testing, and even (gasp!) development.
Most Open Source developers are actually paid for their work. IBM, Apple, Sun, Google, and maybe even Microsoft pay developers to work on various Open Source projects.
Some Open Source projects (like Joomla) are run by the very people who use that software in their own jobs. Some like MySQL are created by companies that decided the best way to make money was to get their product used by millions of people and then make money through training and support.
All Open Source means is that the development team decided to make the code freely available to the world, and there is a wide variety of reasons for doing that. Sometimes it is purely done for philosophical reasons, but most of the time, it is for strong business reasons.
I don’t know much about the Windows Open Source community, but in the Unix world, you couldn’t even start coding without Open Source projects. At my work, our development team depends upon Linux, Spring Framework, Subversion, Eclipse, Apache, Tomcat, Hudson, and probably another dozen or more Open Source packages.