From another blog, but ..... it made me think twice.

the cool hunter - SUPERMARKET CART - CHARITY AWARENESS [thecoolhunter.net]
This action consisted of three different child faces of ethnic backgrounds: Asian, Black and Indian. The mouth had an opening just where the coin to release the supermarket cart is inserted. Each coin would symbolically feed a child. Under the image, it says " You can feed a child for two days with what you spend renting this cart. HELP