anybody notice the pretzel theft?

in the first scene in front of the skool,
as the 3 actors walk by a boy one of them snags his bag of pretzels and continues walking down the sidewalk eating from the bag,
behind the main actors the boy goes up to some older guys and seemingly tells them about the theft and they get up from the grass and casually follow the 3 main actors until they stop,
the actor who took the bag looks back at them and acts goofy and puts the bag down and the scene ends,
can't tell if it were scripted or just smth 1 actor impulsively decided to do