Suzanne Collins said this quote

“ In theory, sure, Gregor could still go home. Pack up his three-year-old sister, Boots, get his mom out of the hospital, where she was recovering from the plague, and have his bat, Ares, fly them back up to the laudry room of their appartment building in New York City. Ares, his bond, who saved his life numerous times and who had had nothing but suffering since he had met Gregor. He tried to imagine the parting. Well, Ares, it's been great. I'm heading home now. I know by leaving I'm completely dooming to annihilation everbody who's helped me down here, but I'm really not up for this whole war thing anymore. So, fly you high, you know? Like that would ever happen. ”