What lessons does Santiago learn by working at the crystal shop in The Alchemist?

Santiago learns a bit about Personal Legends and omens from the crystal merchant;
however, I do not think that is the most valuable thing that Santiago learns from the crystal
merchant. I think the most valuable thing that Santiago learns is a lesson about the importance
of action and actually seeking out his dreams and Personal Legend. Through the crystal merchant,
Santiago gets a very good example of what a person looks like and/or becomes when dreams stay
dreams and action is never taken to attain the dream. The crystal merchant has his own dreams,
but he is unwilling to actively do anything about them, and it is for a silly reason. He's
afraid that if he realizes his dream, he will have no motivating reason to keep on
living:

Because it's the thought of Mecca that keeps me
alive. That's what helps me face these days that are all...