Official Stories display a custom Snapchat emoji so you know that the account has been verified. This is reserved for celebrities and other public figures.
The number of verified Snapchat accounts changes all the time. This page lists all currently active Snapchat accounts with an official story emoji.
Snapchat Story Emojis
Snapchat emojis for official stories are customized for each person, so one might show a loaf of bread, while the next will show a cactus. This is what the official story emojis look like for verified accounts:
Learn more about Official Stories from Snapchat Support.