Personally, it's always a bit wild to me to see commentators interact with the Hunger Games franchise as if Collins were writing science fiction stories instead of essays with faces. She's just not that interested in fleshing out side characters or digging into the details of the worldbuilding. These characters are concepts and symbols before they're people. There's an almost mathematical precision to who and what she explores and how deeply she does it. This is a step or two away from pure allegory. If she were writing a couple of centuries ago, she'd have named her characters things like Innocence and Anger and Watch-Carefully-Your-Soul-Lest-Ye-Be-Damned, but since she's writing for modern audiences, she has to settle for puns and allusions. If she has another essay to write, she'll assign some faces to it; she's not going to look into backstories or other eras just for the sake of storytelling, and it's not a failing as a writer that she doesn't.