And I'd argue that doing something for profit is also against the spirit of open source, but that's a different argument. The thing is that open source is for the most part an effort from hackers, hobbyists and professionals who want to foster a positive ecosystem for people like themselves. To make their passion better and simpler and more fun and more accessible and more interesting and safer and more efficient and more general... So that more people might fall in love with it.
It's not to push a product or to convince people that they need it. And that sentiment comes from the fact that open source is the reason many people got into programming in the first place! Thanks to all the free resources out there. So they want to give back to the community. That's how I feel about it at least.
But then again, when huge corpos contribute to open source it's great because they have a lot of inertia. So I think that's a good thing, it's a positive feedback loop. My previous point is not black and white, even though I am obviously bitter about a lot of things.
The idea really isn't so far fetched, lots of projects today have non-legal outlines of expectations of community members. For a single example, codes of conduct are very common.
Again, this thread is about whether we as a society, or as the software development community at large, consider the behavior ethical or not. It is not about the specific open source developer imposing specific rules.