The lady is setting up the bags of treats for Halloween. Some of what the goodies she places into the bags aren't simple pieces of candy. They are beautiful diamonds that sparkled in the light.
We see in a closeup view a woman's hand dropping candy from her hand to the bags of two children in Halloween costumes extending out empty sacks hopping for tasty treats. But as the candy gets to the bag the candy turns to diamonds, sparkling and glittering in the moonlight.