why are their faces frozen in terror?

I saw this at Sam's club yesterday and was so confused.  Is this really the best picture they could have chosen?  I mean, it's photo paper, they literally could have used any photograph of anything and they decided to go with three children, each more frightened than the one before?

And they are all looking at different things.  I assumed it was a zombie apocalypse that had ruined that little girls birthday.