In this heavy-handed fable, the Ole Goat of Grede Mountain (Grede Mountain, get it? Boy, I almost missed that, it was so subtle) has a black bag which grows ever larger to accommodate his insatiable desire for stuff. The goat robs all the smaller animals but eventually by a bear who has no possessions except his clothes. The bear (long-time symbol of the Soviet Union) leaves him submerged in mud with a bag over his head, which I found creepily reminiscent of images of "enemies" captured by terrorists.
A blurb from Kirkus asserts that this is a Native American legend, but the book itself doesn't indicate any origin.