Why does Finny begin hitting his teammates with snowballs during the snowball fight?

Finny begins hitting his teammates with snowballs during the snowball fight as an expression of his playful and competitive spirit. He enjoys the camaraderie and excitement of the moment, seeing it as a way to bond with his friends. Additionally, this action reflects his natural leadership qualities and desire to engage others in fun, highlighting his charismatic personality. Ultimately, it's a manifestation of his carefree attitude and love for friendly competition.