I'll clarify. I meant that people are entitled to their own emotions, and being angry is ok. What's not ok is to hurl the anger towards somebody. In this case, there are lots of other good options, all of them more productive and compassionate than simply grabbing the pitchforks.
No, you do have the right to be angry, even for something you’re not paying for. Absence of a financial agreement does not mean dissolution of basic community norms.
No. You have a right to be annoyed, and then fork the project if you want.
You do not have a right to become angry unless you're paying for it.