Bear with me, now. I have a theory. A completely weird theory but one that holds up to evidence in The Hunger Games books. Oh, and I am also accepting scenes from The Hunger Games and Catching Fire movies as cannon because Suzanne Collins worked on both movies/screenplays. We know she requested more of Effie Trinket in Mockingjay: Part One based on the actress's portrayal of Effie in CF, so we can assume Collins has a decent amount of sway as to what happens in the movies.
My theory? Ready for this? The 74th Hunger Games was rigged to get rid of, or stomp down, Katniss.
I mean, really rigged. Like, the Capitol/Snow knew about Katniss and wanted that chick down.
Why? Well, people, let's go alll the way back to when Mr. Everdeen and Mr. Hawthrone were blown to bits in the mine accident. Oh, yes, I am suggesting that it was intentional.
In THG, one of the first things we learn about Katniss's father is that he hunted with a bow and arrow, items he could have sold for a handsome price but people (Peacekeepers) would think he was trying to arm the Seam for a rebellion. Right after that, Katniss says, "when I was younger, I used to worry my mother with the things I would blurt out about District 12 and the people who rule our country Panem...." (5). She says she learned to school her face, keep her head down and not say anything that could get her and her family in trouble.
So, her father hunts illegally with an illegal bow and arrow and Katniss heard someone unpleasant things about the Capitol. Could her father have said things about Panem that would have had Peacekeepers sniffing around their door? Evidence points in this direction, as we learn in Mockingjay that Mr. Everdeen used to sing The Hanging Tree. He sang it enough that a young Katniss, about six or so, knew the words and sang them to Prim as they played. Her mother overheard them and got angry, angry enough that she scared little Katniss into hiding in the meadow. Apparently, Mr. Everdeen was known for singing this song in D12, as Peeta (coming down from the hijacking) remembers Mr. Everdeen singing The Hanging Tree in the bakery.
If Mr. Everdeen is singing The Hanging Tree, a song that is a punishable offense to sing, what else is he saying about the Capitol?
Hold that thought for a moment. Let's move onto Gale. We know little about his father, just that Mr. Hawthrone was killed in the same mining accident that killed Mr. Everdeen. But Gale is full of "fire" and routinely rants about the Capitol and the injustices of life in D12. We know Gale's smart and, yes, he could have come up with these (justifiable) rants on his own. Like Katniss, he was forced to help feed his siblings at a young age, although Hazell Hawthrone isn't incapacitated like Mrs. Everdeen. Oh, yes, he has good reasons to be mad at the world... but is it possible that he heard the same rants from his father? I say yes, very, very possible.
So we have two people, Mr. Everdeen and Mr. Hawthrone, who have complaints against the Capitol. We know the Capitol has Peacekeepers and possible spies everywhere. Could the mining accident have not been an accident? In other words, was it on purpose to kill two (however quietly) vocal people who spoke out against the Capitol?
Following my theory, two men who spoke out against the Captiol are dead. They leave behind six children, one yet unborn, and two widows. No one cares what happens to them; as The Hunger Games proves, life is disposable. Mrs. Everdeen fades into depression, Prim and Katniss begin to starve, Hazell has a new baby and begins to take in laundry to make ends meet. As far as anyone in power is concerned, the problem is taken care of.
But then! Peeta throws her the bread, she is saved and remembers what her father taught her about eatable plants, she hunts, teams up with Gale and everyone's... well, not warm and completely fed and not totally happy but not starving.
You can almost hear the Capitol face-palming at this.
They got rid of Mr. Everdeen but now they have another problem on their hands: Katniss. Like her father, she's bucking the system by hunting and trading at the Hob. She knows the system is unfair and pits the Merchant class against the Seam- she listens to Gale, after all. But where he wants to actively change the system, she just wants to live in relative peace and take care of Prim. Of course, though, her illegal activities must be stopped. How would you bring down a devoted older sister? Reap her younger sister.
Peacekeepers/Snow want two possible outcomes of the Reaping: Prim is reaped, goes into the Games and dies OR Katniss takes her place, goes into the Games and dies. Even if she wins, which they doubt, they don't expect her to become a role model for a rebellion. As Peeta says multiple throughout the series, and Delly indicated in D13, "[She] doesn't know the effect [she] has." She volunteered for Prim out of love, not expecting the three-fingered salute from her district.
But Snow knew. While Seneca Crane was crowing about an underdog, Snow was all, "Seriously, contain that spark." We see in the movie that Crane tries to follow Snow's orders but Katniss will.not.die. Not fire, not starvation, not the Careers. Snow's probably beheading his roses in frustration.
Crane, though, eventually gives into Haymitch's request and "gives young love a chance." As Gamemaker, he could have flooded the cave but instead Peeta and Katniss get some alone-time to connect. In doing so, they win the hearts of the nation and become devoted to each other. Although they have a small past (the bread) and Katniss clearly thinks about Peeta in the time between the bread and the Reaping, it is possible, without that deeply personal connection, she would have killed Peeta to win the Games. Yes, IF Crane had played the Game according to Snow's wishes, IF he hadn't announced that two from the same district could win, IF they hadn't had those days in the cave to connect, IF Peeta survived the cut on his leg, alone, I think Katniss would have won the Games. Then, of course, Snow would have sold her body like he did Finnick, or something equally as deplorable, or she would have gone mad like Annie Cresta. But all that is speculation, of course- if this, if that.
What IF things had gone according to Snow's wishes? Katniss would have been under Snow's thumb, still trying to survive to keep Prim safe. If she died, Gale would have moved on to someone else, keeping the Everdeen's safe until Prim was old enough to help bring in enough money as a healer or got married. But, of course, everything blew up in Snow's face.
So, two people win the Games, they have the devotion of the Capitol and inspired the districts to stand up against injustice. Crane's dead- Nightlock, according to the movies. Katniss is home, but still hunting in the woods and is thinking of teaching Gale's brother to hunt. She's still friends with Gale and listening to him hope for a rebellion. IF she had gone home and been a good little Victor arranging flowers or whatnot, MAYBE Snow would have left them alone. MAYBE.
Now, I think Snow knows Katniss loves Peeta*; maybe not in a romantic way, but she is devoted to him and we all know Katniss is willing to die for the people she's devoted too. Yet Snow completely plays head games with her, leading her to believe she hasn't convinced him she loves Peeta. That is Snow's MO, after all- head games, or worse. But, the spark was lit and we all know what happened next.
Let's diverge for a moment. Why not Reap Gale? Gale is clearly the trouble maker. He's the one who is out spoken against the Capitol and his name is in forty-something times. No one would be surprised if an eighteen year old male from a large family who took out tessera was Reaped. Think about Gale's personality, though. He would use his time in the Capitol to start an uprising or, at least, plant seeds of one. If Katniss is a spark, Gale is a smoldering fire and it wouldn't take much breath to turn into a wildfire. Whereas Katniss can be contained, everyone knew Gale couldn't. Plus, Gale had much better odds of winning the thing because he's big, strong and thinks like a solider. Yeah, the odds would not have been in Snow's favor if Gale had been Reaped. (Plus, can you see Snow manipulating Gale like he does Finnick? I can't.)
So, yep, that's my theory folks. Snow rigged the reaping to try and get rid of Katniss and everything went so very wrong on his end and so very right for everyone else. Too bad it took loosing so many people and a war to achieve peace.
*This is confirmed in Mockingjay!