It goes back to "Saint" Ara Parseghian running up the score in the 1960s, Dan Devine doing the same in the 1970s with his dislike of Pepper, & so on.
When we played in South Bend in 1970, their "bellhop dressed ushers" were cussing at us on the sidelines. Their seats came right down to field level & the sidelines were barely five yards wide, if that. The ushers spent their energy cussing at us & telling us to take a knee so their patrons in rows 1-5 could see. Even our Catholic players, several of which had been recruited by ND, couldn't believe their behavior. We didn't, they couldn't, so they did.
Dirtiest college football team in that era? Notre Dame.
Just one (ex-Catamount) OldeFarTekker's perspective