I don’t think the book would have been less popular if she’d have been dropped grubby into the arena. It just wouldn’t have setup an important plot point in the 3rd book. The fact is all that “luxury” the gamers get to “enjoy” before the game exists for 2 reasons: TV and guilt. The Hunger Games are a media event and they want to show the glory of the Capital. But also people in the Capital, especially people associated with the Games are starting to question the whole setup especially the Games. Year after year after year they get to meet these kids, then send them to their deaths and it’s starting to wear on them, which (SPOILER) becomes very important in the 3rd book (and really the end of the 2nd) when the rebellion gets going a lot of the people that are driving it are people from the Games.
Yes, the author used Katniss’s growing connection with her makeup team and handlers in the plot. But the primary function of the makeup team was female wish fulfillment. And I am a woman and the mother of daughters.