> I feel the vast majority of people complaining about these kind of situations are people who want the benefit of the tremendous engineering accomplishment of a game engine like Unity without contributing or paying in any way.

I just want to point out that the biggest non-contributors to open-source are the enterprise companies you either never or barely heard about, whose entire stacks run on tons of open source and yet it's those end user enterprise shops that are making millions.

In many ways, this probably includes Unity themselves.