Answer:
The length of the description emphasizes his importance to the story.
Step-by-step explanation:
John Steinbeck's Travels with Charley tells the story of the author on his travels with his dog Charlie. The travelogue details the road trip that the famed author took around the United States with his trusted poodle.
In the stated passage about Charlie, the poddle "contributed much to the trip" which the narrator mentions. The dog is of great importance to the author, stating that Charles le Chien aka Charles "is a bond between strangers". This description of the dog in a much greater length is to emphasize on the importance of Charley to the story.