In 1971, the Keep America Beautiful organization aired a famous TV commercial of a Native American shedding a Single Tear at the sight of litter being dropped on the road (in a follow-up ad, the Indian rides with a big smile through towns where people are cleaning up). It's known as the "Crying Indian" ad, although it is called "People Start Pollution, People Can Stop It". At the time this was quite a powerful ad. Not subtle, but of the Some Anvils Need to Be Dropped variety. You can find videos online of course. Examples of Crying Indian include: