Evidence of Fight Clubs at prestigious schools and a private school which encourages physicality in their charges. Two sides of the same coin. While the feminisation of education through NCEA has shown that girls can do anything, it has left the boys with a head of steam.
Back at Huntley School, a competitor of Hereworth's, the jocks played rugby against each other. Not much of a rugger, I took solace in the unofficial annual bash. At the end of the term, a fight would break out between two tribes. Inevitably, most of the kids joined in. There would be some 200+ kids on the fields having it out. Scores were settled, grudges brought to a head. Boarders would smack day-boys and vice versa. Like square dancing, opponents moved to another scrap regularly. After a reasonable time and before things got vicious, the teachers would close it down.
I doubt this tradition has survived. Like smoking indoors and cycling with the wind in one's hair, it has been outlawed as unhealthy and possibly too mammalian for the cultured psyche of 21st century humanity to endorse.