Comment by acoustics

This might not be charitable, but my perspective is that some of the advocates want it both ways.

I would be interested in seeing an MIT/BSD licensed project saying, from the beginning, something like "This project is available under a permissive license, but I have a strong ethical expectation of my users to give me money if they build a product off of this work. I am fully aware that I can't legally enforce this, but I will certainly call you out publicly for your greed and lack of respect for my wishes."

My hunch is that many advocates would hesitate to put this in their project Readme, because they know that some companies might actually comply... by not using the code. (Call me naive but I think this is plausible.) They would rather give the impression that the code is truly no-strings-attached, because that would help drive adoption. Then later they can come back and say they ought to be given a cut.