One superstar of Hindi film industry is regarded as a very humble person but in reality, he is a hidden arrogant man. Several other actors who were/are equally senior like him were sacked from the industry at his behest, k e such said in an interview that he was sacked because he didn't call him"Sir".
What the author has said is absolutely correct view. Rich people have no respect for poor people whereas a poor person comes with an open heart to help others if he is in this position to help others. If someone helps him when he is needed he does not forget his help and he always remains thankful to that person whoever helped him.
At sometimes I have seen some poor people who behave very arrogantly with others. They may behave very nicely when they need some help from others. But once their work is over they may not be good with the other people.
More than the financial status, the mentality of the people will have a lot of impact on their behaviour. Percentage of proud people may be more in rich and less in poor.
Thoughts exchanged is knowledge gained.