I've spewed up once at sea during a "Thursday War" drill up in the pointy end of the ship in rough seas at speed during action stations as damage repair crew, once one person vomits and it starts swilling about it causes a bit of a chain reaction amongst everybody.
I liked being at sea in rough weather as the queue for dinner was non existent and most of the crew lay strapped into their bunks to prevent them falling out/getting hurt so nobody around to bother you, no stupid exercises or drills either just us sat in the control room looking after the engines and hanging onto the walls and the poor bridge crew being flung about upstairs.