My hubby got a new assistant to help him with the grocery work. Little Luffy is very keen with the trolley. He will push the trolley, any trolley that he stumbled on. This happened a few times at the store where I have to apologize because he simply push other people trolley. He would cry if we stop him or if the trolley wouldn't to move.
See this video, Luffy helping hubby pushing trolley to car. On the way back he did push this fully loaded trolley. However he still need assistance on the direction :)