Why do you think it is that many criminals value their dignity over anything else?

 i think many criminals value their dignity over anything else because they don’t want to seem like a pansy, in their eyes they believe losing your dignity is just as equal to dying 

You'd probably do better to move this to psychology or sociology, but I'll give you my guess anyway. It seems to me that they actually have nothing else to focus on. Most criminals(with the exceptions of some of the elite) come from the extreme lower class. They generally have no education to speak of, and a large percentage of them are functionally illiterate. They have no property, and often no family, at least one they can interact with. The only thing they can carry around with them, whether in or out of prison is their fictional self-esteem.