You say you don't need presentation skills? You're not a public speaker? Think again.
Beauty pageants aren't just about beauty. Did you know that the interview is 40% of the grade? That means if a contestant flubs the presentation there's a good chance she won't win the crown.
It's no different in business or the workplace. I've known very bright, competent people who lose instant credibility because of an inability to communicate or speak in public.
But don't take my word for it. See for yourself.