What evidence does this chapter provide that the plan to release Jim is little more than a game to Tom?

Tom is having Jim do elaborate things that were mentioned in books.  These include keeping wild animals, inscribing a crest on the wall or millstone, and growing a flower in his own tears.  In addition, Huck and Tom take Jim out to help move the millstone.  The plan could have been done quickly, but Tom wants to play the game.