Boobs = Brains?!

I found this picture from one of my school mates having it as a profile picture. This trash can is located in the United States. So the question is: why its on a trash can? Is it that men will be attracted to the trash can and throw the garbage? Clean environment by creating sexual images? The idea isn't really clear to me. Although if they want clean streets, they should put a wet t-shirt for the men's sake. After all men never think with their brains.