Cereaiously?
Is it possible they started selling cereal boxes at the movies and we never noticed? Seems more likely that this group of friends decided that they had enough of popcorn, and they want to start a new trend of movie snacks. They brought it complete with the mild and everything.

Cereal can certainly be a great snack, the only problem is, last time we checked people weren’t allowed to bring outside snacks to movie theaters. They have a variety of snack to choose from at the theaters, and bringing outside food – and leaving it scattered on the floor like this – is wildly inappropriate behavior.