The local tradition of Fionn makes him out as a giant and kind of a buffoon. There is a story which I heard as a child where Fionn challenged the Scotch Giant, and seeing his size lost courage (the Giants' Causeway is said to have been built by these two).
His wife, seeing his quandary, put him in the cradle and pretended that it was the child. She fed the Scotch Giant with oatbread in which sandstone flags were placed. He asked was that Fionn's usual food, and on being told that it was, got frightened in turn and left.