Question: why do friars have that haircut?
Answer: Tonsure (/ˈtɒnʃər/) is the practice of cutting or shaving some or all of the hair on the scalp as a sign of religious devotion or humility. ... Current usage more generally refers to cutting or shaving for monks, devotees, or mystics of any religion as a symbol of their renunciation of worldly fashion and esteem.