Why should people have to work for free? I have a skill, I expect to get paid. I don't see my plumber doing pro bono work at the weekend.
Not everyone has to adhere to your philosophy. You license your code for me to use, that's your prerogative. Don't complain when people don't give anything back.
To paraphrase your last paragraph: "If your ideal system allows parasites, you're not entitled to use mechanisms (e.g. social stigma) to control those parasites."? Complaining about parasitic behavior is a form of social control. It actually comes part and parcel with the open source license. If you don't like people talking bad about free loaders, stay away from the open source community.
"Beneath the appealing, easy-to-use interface of Mac OS X is a rock-solid foundation that is engineered for stability, reliability, and performance. This foundation is a core operating system commonly known as Darwin. Darwin integrates a number of technologies, most importantly Mach 3.0, operating-system services based on 4.4 BSD (Berkeley Software Distribution), high-performance networking facilities, and support for multiple integrated file systems.
Darwin 1.4.1 is the UNIX-based, open-source foundation of Mac OS X. It is based on FreeBSD and Mach 3.0 technologies and provides protected memory and pre-emptive multitasking. This release corresponds to the release of Mac OS X 10.1."
If a company decides to open source a project that is not directly related to their business, then they are gaining an advantage - now their code can be vetted and improved by the open source community and they can spend less engineering time on the project themselves while they focus on their real business.
Where is this magical "open source community" which is eager to examine dull business code? It's a myth. The Debian project shipped a broken PRNG for ages, and that is a popular project.
Who ever said 'dull business code'? Take Twitter Bootstrap for example - It started off just so Twitter could iterate faster on internal applications and not worry so much about styling - Now they've open sourced it and others can contribute. It does nothing to better their business model.
>It's a beautiful story for a person caught between childhood and adulthood
I could say the same thing about every religion, I doubt it would get a warm response.