Coming from a diocese that was quite progressive, I have seen my fair share of illicit behavior, and some abuses in the past that were usually rectified pretty quick, so long as the right people knew. Many of the parishes where these things would happen did not have membership that had the Bishop on “speed dial”.
That said, some of the worst abuses I have seen are those of the laity toward the hierarchy. People who ride their pastors with mundane and ridiculous demands, who publicly call their priests/Bishops with whom they don’t agree, heretics, spreading vicious and destructive lies about people, priests, sisters & Bishops, etc, etc, etc.
It’s a very sad state of affairs, and a perfect example of why young men & women shy away from the priesthood and religious life, at least IMHO.