Regardless of whether or not you wear a hat while you jackhammer, you’re going to have a surplus of noise. Jackhammers are loud, and your hat is doing nothing to dampen the racket. There’s a surplus of commotion coming from the jackhammer and onlookers are not amused.
One of the people walking by is the owner of a push cart yo-yo (よ) stand. Having a surplus of yo-yos, he starts throwing them at you. This makes you stop using the jackhammer as you need both hands to fend off the yo-yo barrage.