I looks as if we're seeing cargo cult approaches to open source.
There have been a few successful approaches to this:
1. Work for what you see as the common good, expecting and receiving minimal rewards - works as a full-time developer if an essentially hippy lifestyle is OK for you.
2. Work for the common good but produce something which is of sufficient value to business users that they're prepared to fund you.
3. Offer some OS-related service such as support on top of your OS work.
4. Use OS to provide some non-OS related product or service and feed back your own contributions, essentially sharing development costs with others who might even be your competitors.
What appears to have happened is that people have seen OS work for others and joined in as creators or as consumers without understanding what makes these approaches work and indeed, without understanding that OS development really involves contributing to a commons.