pardoners tale

In the pardoners tale,  the tale is seen as a riddle to me. He discusses 3 rioters that try to kill death. This in itself is very stupid to me and amusing. I already know where this is going. You can't kill death. And then an old man directs them to under an old oak tree and say that's where they can fund death. If I were one of them I wouldn't take another step. This is obviously their demise. And death is 8 bushels of gold coins. This gives off the warning of greed and nothing is prospered but death. It's proven when 2 of them plot to kill their fellow companion. Lesson learned there are no friends where greed is present.