Procedural Rhetoric and Theme in The Walking Dead

I've been thinking about procedural rhetoric and its relationship to a particular theme in a story. For example, a major theme in The Walking Dead is humanity: how do you maintain your humanity in such trying times, and how far are you willing to allow it to slip in order to survive?

How do the game’s mechanics support this theme? Most of the mechanics are superficial in their relationship to the story (i.e., classic point-and-click adventure style of interaction). But then there are the story choices. Many are dialog choices which don’t end up having much real impact in terms of story results, but some are black and white choices like whom to save.

These latter types of choices seem to fit more with the idea of procedural rhetoric. You are faced with a decision you have to make quickly and on the spot. Neither choice is good, and sometimes the outcome is essentially predetermined anyway in the sense that the zombies will kill no matter what. This reflects how it might feel in real life as well, when the adrenaline is pumping and you have only moments to react. Sometimes your actions feel futile, and often somebody has to die.

But I think these are really the only mechanics you could argue represent procedural rhetoric relevant to the humanity theme.

I want to figure out if there's a way to represent the theme more deeply in the game’s rules/mechanics.

SPOILER ALERT...

For example, one episode involves a farming family who we eventually learn are cannibals. They had decided to survive by eating flesh of people who were injured and going to die anyway, though they eventually rationalize eating even hardly injured people. How could the game reverse the roles so the player ends up doing something like that and actually feeling like it was the right choice despite the moral dilemma?

...END SPOILER

I want it to be more than just the story, even if the story can branch for these kinds of choices; I want the rules of the game to represent the theme better. I am not convinced the current setup of Walking Dead would be the best for this, given the style of mechanics, so what might?