Please pay attention that our member only claimed it might be sanctionable. In no way did he implied he is going to report you and even tried saving you from trouble in case someone else wanted to report you. I believe this is kind and warm gesture, which you misinterpreted.
Such behaviour isn't frowned upon and doesn't bring shame to 5th. Being helpful is one of the features all member should have.
However, the way person chose to express his concern is indeed a little bit over the top, much like overusing capital letters.