Old man guru archetype

I thought that Mississippi Gene, with his tendency to distribute worldly pieces of advice, sad easygoing view of the world and even taking a younger person under his wing for protection of sorts , especially with Gene's long years of suffering fitting into the lifetime of hard experience as a janitor/hobo/family- and friendless person with no purpose in the world, which drills into the person the knowledge needed to survive in a harsh cruel uncaring world, all fit him pretty clearly into the "old wise man" role that is repeated frequently in contemporary literature (novels, movies, etc.); these characters always then somehow gives the main character a sense of purpose/greater understanding of the world/valuable insight into themselves. Is there a possibility of him actually having some greater effect on Sal later in the novel, even as just an emotionally touching memory, or will he be totally forgotten as a meaningless single encounter on a hitchhiking trip?