What I experienced seemed to be considered such a norm at many Catholic schools across the country that there’s even inside jokes about how Catholic school students are often subjected to much more serious punishments…including expulsion for disciplinary infractions which would likely get a slap on the wrist or even ignored altogether at public and some non-Catholic private schools.
Also, while they may not usually resort to long-term suspension or expulsion of students for relatively minor infractions…they all reserved the right to do so.
The ones in my area, ones HS/college classmates/colleagues attended not only in NYC…but also around the nation, and the parochial HS my younger Mississippi cousin attended used it when they felt a need and reminded students/parents to drive home the point and as a selling point for parents looking for a more disciplined school environment than the local public or other private schools.