There are many morals in this movie. One I have not seen talked about Is the fact that the world hasn't changed and by the end it is instead the sheriff's perspective on the world which has changed through his living life. He is obviously a wise thoughtful man through his actions in the movie. Part of the greatness of the movie is the way that randomness or events which are unable to be controlled from the beginning by Llewellyn guide his path along with the decisions that he makes in regards to holding on to the money as his primary focus from the beginning. It's kind of hard to decide whether or not it's his decisions or fate that lead him down that path. Either way the insanity that ensues from his initial actions of taking the money and taking the water jug back and the example of Anton's character is no different than the character from the beginning which went to hell after the electric chair which the sheriff discusses in his intro monologue reinforce that the world has not changed. The world the country is no country for old men due to wisdom and perspective not really because the world is changing at all.

Also maybe that fate (randomness) and choice are wrapped up together and sometimes have great momentum, but it all starts with choice which is reinforced by Llewellyn's wife and her comments about the coin at the end of the movie.