Much is made in the book of how the lead character, Christa, does not eat junk food. So why does the cover include a lovingly-rendered packet of Doritos sticking out of her backpack?

Editor's Note: Normally, a discrepancy between a book's cover and its content are not considered slip-ups. However, in this case I can see why this should allowed. If there is a logical explanation for it, then the readers will correct it.