The initiate has to pass some sort of test to prove his worth and eventually saves the day. The same happens to Bilbo except he proves his worth many many times. The fact that Bilbo is the initiate in this story makes a tremendous difference. His character on the inside and outside slowly transforms throughout the whole book. If he did not go on the journey, the dwarves would have probably failed their mission.
Many alternate characters exist as initiates.
The initiate archetype is very important to society today. It forms the backbone of many stories, poems, and movies. It explains to people that they can do anything if they practice and set goals. The initiate can also take the form of a college student. The student needs to pass through the arduous tasks of college to get to his goal of the degree.