This pin uses typography to form the shape of a bottle, which relates to the chocolate milk metaphor it uses. It is an advertisement against drugs, and it wouldn't have as much meaning or be as unique without the cartoon-ish text in the bottle shape.
This design is great because it's free flowing and and the lettering has a lot of character. I like the way it flows down the bottle and the work is broken up into sections rather than stretching it horizontally across the bottle. The light lettering against the dark background creates a lot of contrast within the design.