It is uncouth to defecate in public.
Barry is walking down the street when he gets an urgent need to defecate.
Barry needs to find somewhere to go to the bathroom.
Barry decides to clench his cheeks and waddle into the nearest store and use their toilet.
Barry decides that he can't risk finding a real bathroom and goes right there on the street.
The people on the street aren't subjected to any of Barry's waste or odors.
The people on the street are utterly disgusted as they all scatter and run away.