> Assuming the terms and prices are fair and no "bad practices" [...] no excessive EULA/DRM
I think there's an argument to be made that the work that compilers perform might as well be DRM. Granted, the obfuscating effect of source-to-binary translation is in most cases incidental to the compiler's main purpose, but it's an effect that can be felt nonetheless.
If there's a bug, the user can fix it only if the source code is available.
> It is like people going to the cinema expecting to be given all the details, including technical documents and whatnot about how the movie was made.
Well, movies do include credits, detailing who did what. From there, you could research what the "what" is and know more or less how the movie was made.
Disclaimer: I have no care either way between OSS or commercial software, beyond liking to contribute and support OSS projects, and working on proprietary applications (and being generally ok with it). So I'm replying not with an intent to proselytize; just thought I could address your points.
I think there's an argument to be made that the work that compilers perform might as well be DRM. Granted, the obfuscating effect of source-to-binary translation is in most cases incidental to the compiler's main purpose, but it's an effect that can be felt nonetheless.