Thrown Ice

Was on a boat with someone I used to know well. It was docked then I started steering it then it halted all of a sudden, so I steered it back to the dock. Then the person that used to be my friend is drinking a cup of water full of ice and just throws the cup across the boat, making the ice fly everywhere. We laughed but the whole time I thought what in the hell are you doing?

Thanks this baffles me

Jesser