The very nature of this question is too black and white thinking. If you are poor, do you work harder or not as much compared to a rich person? What about the grey area? Is it fair to say that there are poor people that do not work hard? Yes. Is it fair to say that there are poor people that work 60+ hours a week? Yes. Is it fair to say that a rich person does not work hard? Yes. Is it fair to say that some rich people work very hard? Yes!
I will give you two examples of a rich person either working hard or not working hard. I have a person from my high school class that is going to law school. He shared with me during our high school reunion that after law school he is going to start a venture capital firm. How is he getting money to fund this firm? His father. His father is on the executive board for Sprint. There are rich people that started a venture capital firm that earned the money required to start such a firm. This kid has his father send him all the money. That isn't really working hard.
On the other side of the spectrum, during the days when I was doing remote desktop repair, I would run into people's homes ranging from the lower class to the ultra rich. This man was so rich (and not married) that he lived in a neighborhood where golf courses were literally down the street. You walked in his home and he had the works. Heated and cooled floors, networked window shades, and glass that would respond to the sun's light. And so I stated to ask, how did he get to this point?
I can't remember exactly what he did, but he said it was an average for him to have fifty hour work weeks. He invested heavily in his retirement, and well it paid off. But he worked his butt off, to the point he said he had virtually no social life. And it showed, because he had no children and no spouse. I could tell he was very lonely living in that huge home all by himself.
On the other side of the spectrum, you hear of single mothers working two part time jobs to put food on the table. You also hear of people on welfare opening their legs so they get more government money.
What I am trying to show is this question is too black and white. You really have to examine the grey.