I agree with the basic silvermountain diagnosis; the only partial solution that I can think of is that developers should ask for money more often (and asking isn't the same thing as insisting). I was delighted when the Liqbase developer requested donations, and I quickly gave what I could afford.

I guess the reason I think that might help is that it could foster more of a sense of responsibility from developers and users alike.

I don't think that the "well, if you aren't happy start coding!" suggestion is seriously meant. I think it's actually designed as a good excuse for the current situation.