I guess this nice parable might serve as an illustration of an aspect of dukkha, a buddhist concept which roughly translates as one's suffering from clinging onto impermanent things and from the ultimately insatiable nature of our desires. These notions are basic tenets of most buddhist traditions which propose some form of abnegate and ascetic attitude in order to overcome dukkha and escape samsara, the karmic cycle of death and rebirth.
From a philosophical point of view, dukkha is an interesting and insightful concept. Many people do draw suffering from being overly attached to something or from having an overachieving, greedy or whimsical attitude. The things we get attached to will invariable be lost someday, with their loss causing us pain. Any unattained desired or unachieved goal is a constant source of frustration and disappointment, again causing us pain. Being able to acknowledge if and how these basic mechanisms are influencing our lives might be a starting point for reevaluating some attitudes and maybe to gradually adopt a more balanced state of mind.
The king's father in the story has taken the radical path of renouncing to any material thing beyond basic needs, and he is trying to warn his son about how one can never be truly satisfied. This is a very typical buddhist message. However, I believe that the key for dealing with dukkha is not necessarily to become an ascetic, but to be conscious of the way we are affected by attachments and desires, and with that consciousness finding a balanced attitude that allows us to really enjoy life to its fullest. Some may end up deciding that theirs is the ascetic way, but for most people I believe it is mostly a matter of adjusting attitudes and expectations.
This is a great contribution to the story, @jmorais! I totally agree that one shouldn't necessarily become and ascetic, but to be aware of this constant need and to find the balance.
Very interesting, I'll be following you for more :)