I suppose that the most obvious answer is that Mr. Parsons is a man who has worked hard to get ahead. On the other hand, the beggar, Markwardt, is someone who has presumably chosen not to try hard and get ahead himself.
We can see this because both of them started out from the same place. They worked in the same factory and were both blinded in the accident. But Parsons did not pout -- he worked hard to get where he is now. Markwardt, on the other hand, not only decided to pout but he also made up a story about how the other man had caused him to become blind (when Markwardt was really the "bad guy).