I disagree with equating whistleblowering and snitching. We all have dirty secrets, but let's loosely say that the scale matters.

It is a different story when coworker tells "boss" who is lazying around, and a different story when someone reports a serious misconduct towards other people. I'm not sure how to phrase it clearly, but generally I would not associate myself with former people, but I wouldn't mind the latter. Maybe one day they'd prevent me from doing something really terrible (given I wouldn't know better).