He is trying to be the perfect father, the father that he always wished that he had himself. He is the type of father that any child would want. I think that this movie was such a hit because there are so many children out in the world today that don't have a steady father figure. More and more parents are getting divorced so the child only get's to see his or her father on the weekends or holidays. On the other hand some of the children that do have fathers don't get to see them all that much because they are too busy working.
Work consumes many fathers lives.
When a child is in this situation they imagine a father that is perfect and that is always around. When the symbolic father is absent it leaves a hole in the childs life that is replaced by an imagenary one.