If you were standing on a skateboard in a vacuum and threw a bowling ball as a means of propulsion, then surely you would need to be carrying another bowling ball to throw in the opposite direction to get back again? I've never seen even one bowling ball in any pictures of the Apollo missions. Case closed.
I just went outside with a large rock and a skateboard threw the rock and didn't thrust backwards or forwards. Who the **** has a bowling bowl in the house outside of America ?