I imagine the pitch meeting went like this:
Studio Executive: Gee, the fans aren't getting excited for this new Jumanji movie, no matter who we cast for it. Any ideas on what to do?
Karen: Well, this is just something off the top of my head, but back when I did Guardians of the Galaxy, the original costume design called for me to bare bellied. Since so many fanboys think I'm dead sexy, why not use that to our advantage and have me running around in the jungle with a cropped top?
Studio Executive: Brilliant! Go with that!
http://www.imagebam.com/image/bcb63a505664664 http://www.imagebam.com/image/b80ae4505667258