Please can you give me the reference to this hadith. I know a authentic hadith does exist with similar texts but says "pride" and not "honor" meaning anyone with even an atom of pride, and who lacks humbleness will not enter paradise.

That said I do agree with you that ignorance and committing evil acts do occur among Muslims, and that results in innocent people being killed. But again the God I worship, the Prophets I have faith in, the Quran and hadiths I follow do not support these acts.
Islam does support capital punishments yes. But they are for cases like murder, rape, sexual abuse of children, and the likes. Certainly NOT for the case mentioned in the OP.