I think that Collins is also trying to tell us about the importance of selflessness and willingness to sacrifice. Many of the characters (notably Katniss and Peeta) are willing to do things that put themselves in grave danger just to help others. I think that Collins is trying to tell us that this spirit of selflessness is a needed antidote to some of the problems of our modern society.
I think that Collins' motivation for the novel is an interesting reflection of the message that she seeks to deliver in it. In seeking to outline the idea for the novel, Collins admits that there it arose from a modern application:
Collins says that the idea for The Hunger Games came from channel surfing on the T.V. On one channel she observed people competing on a reality show and on another she saw footage of Iraq War.
Examining both concepts reveals a great deal. A war with human cost and savagery, televised and sanitized for television, along with the emergence of reality television, where everything is contrived under the guise of "reality." It is here where I think that the theme of the novel emerges. In a world where so much is scripted, even life and death, there has to be some universal and permanent values. I think that harvesting both of these ideas can bring out much in relevance to her work. Reality television has created a generation of viewers who see conflict as a voyeuristic sport of sorts. The question Collins raises in her book is that if everything is scripted, and all of life's interactions are on a screen to be viewed by everyone, there is significant question as to what constitutes "the real." The fact that she sees the televised footage of the Iraq War adjacent to reality television is very telling. Even war, the mot horrific of human interactions, has been reduced to reality television, where smartbombs and daily tallies are seen in some sort of twisted reality script. If everything is scripted and contrived, where do real and valid human emotions fit? It is this paradigm that she uses for her story. Collins' uses Katniss and her predicament to highlight some of these values such as friendship, loyalty, and defiance in the face of a moral and political wrong. The theme becomes this idea, one that seeks to awaken a sense of resistance in a dormant people, similar to how Katniss seeks to bring out lasting change against Panem and oppression.