Hi, Wavydaniela :)
When someone tells a poignant story about living in a squalor, the moral reason that I could think of is that he wants to inspire someone. People would get motivated when a rags-to-riches story actually happens in real life. He might recall his early struggles and how he won over them to make them realize that as long as there is hope, you could always rise up and recover.
I hope I was able to answer your question :)