No merchandise shall be displayed upon the sidewalks
of any public street, except glass-enclosed cases or stands used for
the preparation or display of sale of popcorn, peanuts, confections
or similar merchandise, provided that no such stand shall extend in
excess of 24 inches from the face of the building adjacent to which
same is placed, nor in excess of 30 inches parallel to such building
face, and provided further that no such case or stand shall obstruct
the free use of the sidewalks for public travel.