Somehow the grub manages to actually look fairly dejected by the thought that there wasn't any candy. His head(and hearts) sink for a moment as he looks at the tiny, yet empty, saddlebag attached to him. After a moment though he seems to get an idea and starts scratching in the dirt. If Blanche at least waits a bit she'll see him write out C6H12O6 on the ground next to him before looking back up at her.