Many people don't like releasing their works under an open license because they do not want other people to make money with their effort.
Of course this is perfectly understandable, as this phenomenon is a real plague in the retrogaming world. I have probably released more retrogaming-related open projects than everyone else in the world and I can tell you for sure.
Again, this is probably due to the scarce knowledge of what "Open Source" really means. The vast majority of the retrogaming community thinks that it only means "free gerbers, do whatever you want with them". It's much more than that, actually: OSHW is a way to make a project through small contributions from many people, where everyone does a little bit and the project improves. The liberty of making money with the product is necessary so that any effort gets compensated.
Like everyone who shares the open source ideals, I don't mind if people make a *fair* amount of money with my work. I have my own daily job, I do these things for some odd kind of fun and because, as I already said, I love the Amiga (and other Commodore platforms in general) and I want to do what I can to help it live forever.
I am far more interested in that the Openness of my projects get leveraged in what I feel is its primary purpose, with other people taking my work, studying it and improving it, or using it as a basis for their own projects (which will stay open in turn, because of the "virality" of the license I chose). This has happened a few times in the past, and made me very happy.
Then comes the bad part, where someone just takes open projects, sells them (often at crazy amounts) and never bothers making a donation to the original author or supporting the project somehow (or maybe just saying "thanks"!). They only care to make as much money as possible while the moment lasts. Sometimes they will even remove the original credits and present what they sell as their own product (which goes against most OSHW licenses). The Amiga "community", in particular, seems to be plagued with these greedy and selfish speculators.
In fact, there are way more speculators than people making "good" use of my projects. This is what really killed my willingness to make more OSHW.