Libre is a prerequisite, gratis isn't. This is an important distinction to make. While it is true that this software seems to be neither, it is important to note when we try to convince them to release it free, we mean libre and not necessarily gratis. (Although the two often go hand in hand.)
When people hear us complaining about it, they often think we want to avoid paying money for it. This is false, and a bad impression to give. That is the purpose behind making this distinction.
According to the free software definition [1], it's one of the essential freedoms:
>The freedom to study how the program works, and change it so it does your computing as you wish. Access to the source code is a precondition for this.
Absolutely not. Anything less than the 4 freedoms is unacceptable. If the program is discovered to be spying on its users and users are not allowed to modify and redistribute the source code then there is no way to fix the problem.
When people hear us complaining about it, they often think we want to avoid paying money for it. This is false, and a bad impression to give. That is the purpose behind making this distinction.