Final answer:
The protagonist aspires to work on a steamboat for the social status and recognition it would afford him, indicating that the greatest reward of such employment is the distinction and admiration from others.
Step-by-step explanation:
Based on the passage from Mark Twain's Life on the Mississippi, the greatest reward of getting a job on a steamboat is the distinction and admiration one receives, seen through the envy of the protagonist's 'old comrades' and his own desire to be conspicuous while working on the steamboat. This desire eclipses his previous contentment with his father's status and reflects his longing for recognition and the chance to stand out in his community.
The protagonist fantasizes about various roles on a steamboat, each more visible and prestigious than the last, indicating that his ultimate goal is the social status that comes from obtaining such a job. However, his admiration turns to bitterness when a peer achieves this dream, and the protagonist is left feeling that his virtuous life did not yield the rewards he feels it should have.