Violence was much more socially acceptable as a response to slights and insults.
Also living conditions were poor and urban populations were highly concentrated and lived in close quarters.
In universities specifically you had very high concentrations of socially highly privileged young men (generally they had legal immunity and could only be prosecuted by the church courts) with a lot of time and energy on their hands.
Because it means a whole percentage of the population never reaches adulthood in medieval times, they die in duels on perceived slights or are.. Strutting around as legally sanctioned murderers snarling at the commoners.
Also living conditions were poor and urban populations were highly concentrated and lived in close quarters.
In universities specifically you had very high concentrations of socially highly privileged young men (generally they had legal immunity and could only be prosecuted by the church courts) with a lot of time and energy on their hands.