Calling it "Narc" at all makes me feel like whoever is speaking will end up in jail someday. The only time I've heard is used it was a threat against me by a schoolmate who didn't want me to tell the teacher about anything when I was in high school.

If you call someone a snitch, a narc, or any similar term, I have zero empathy for you. Reporting people who break the law, within reason, should be encouraged promoted and congratulated.