I don't know about Cardassians, but their homeworld seems to be rather devoid of natural resources, so maybe hunger can be a reason for that. Coupled with their emphasis on family, it seems that their expansionism is rooted in the the deeply-felt cultural need to ensure that their family would never feel hungry again.
Indeed. I still think there's a sense of victimization in there, though. I think on some level the Cardassians are angry at "god". They used to be a religious, spiritual people; then their climate and natural environment apparently went cataclysmic on them. "God" betrayed them. In Trek lit non-canon terms, Oralius betrayed them. So they destroyed the peaceful church and set up "strong leaders" who kept the people feeling safe and dignified and powerful at the expense of any real safety or dignity or freedom, either for the Cardassian populace or anyone else the Cardassians moved against in their desire to find resources.
Everything they do to "protect" and "safeguard" Cardassia and the Cardassian freedom actually crushes the Cardassians and everything Cardassia used to be. And eventually, those same measures justified as safeguarding the Cardassian populace indirectly lead to half that population vapourized in a Dominion bombardment.
EDIT: I also think this "god betrayed us" idea- unconscious now, likely- explains Cardassian disdain for Bajoran faith. The weak, deluded fools! Don't they know they can't trust their precious prophets to take care of them?! I'll prove it! There! Gul Darhe'el just kicked you. Where are your prophets now? Let that be a lesson in life...