I also believe that proprietary software is morally wrong. I do not care if it has better performance or features; it is just unacceptable on principle. If I'm a fundamentalist for this belief, so be it.
Well, using the term _morally wrong_ seems to paint you into a certain corner. I am curious: where do morals come into play here? Why is a written piece of software so much different than, say, a chair that was built by a carpenter. Would said carpenter be morally wrong as well if he did not want to show you how to build the chair? I am _not_ trying to start an argument here---I am honestly curious about your perspec…
I want to be able to check whether the software does anything harmful for me, and to be able to fix it and adapt it to my needs. Proprietary software effectively curtails the possibility of doing that.
Say I am allergic to nuts. Fortunately, when I buy some processed food I can check easily whether it has nuts or not. Now imagine living in a world where food makers sneakily put nuts in their products, in order to "enhance the user experience". And not only that, but they took great efforts to hide this information from the consumers. After all, most people are not allergic, so no big deal here. I would say that this is immoral.