As is your right, you get to set the conditions for using your code, and so does everyone else for their code.

Yes. And in some cases I think it's a weird choice.

If a large, complex program is developed under a permissive license, and the developers decide to add a small GUI using PyQt4 - they would violate the GPL. Because of that, someone developed PySide as an alternative.

If a language is developed under the BSD license, and the developers decide to use libreadline for improving the interpreter REPL - they would violate the GPL. It's not as bad as the other example, but it still odd to impose those restrictions as a library.

For libraries or frameworks with a big scope, e.g JUCE for DSP development, I can understand why they dual license with the GPL or a moderately expensive commercial license.

I'm not following this, AFAIK freeware does not mean that it has to be proprietary, it just means that it's free (as in beer) ?

I mean that I would be the owner of the program, and I would grant the end user the right to use the program in some way I would see fit. The source could released at a later time, where it would possibly be licensed with GPL (like e.g. Id Software has done with their older games).

In addition, permissive licenses doesn't scare away commercial users. Take LuaJIT for example, the permissive licensing makes it usable for a lot of companies who use it in proprietary software. In turn they contribute patches and sponsor the development of new features which improves the language - everyone wins!

It's the same with LLVM. GCC/GDB was the deal-breaker. They crippled the compiler so it would not be possible to extract the AST for doing source analysis (for e.g. code completion), because it could be used in proprietary software. At the same time it made it made it harder for free software to do the same thing... I think the situation has improved somewhat now that they have a competitor.