I wish I’d been in this experiment as a “leader” to see what I’d do, because I can’t imagine taking the cookie without at least asking whether anyone else wante

I wish I’d been in this experiment as a “leader” to see what I’d do, because I can’t imagine taking the cookie without at least asking whether anyone else wanted it, or offering to divide it. I can’t see any of my friends taking the cookie either. Is not having any manners so common?