Before the austerity imposed by World War II, produce in the US was shipped in wooden crates with colorful, carefully designed and illustrated labels, meant to set each producer apart from the others.
The relatively sudden advent of cheaper cardboard boxes left many of the crate labels unused and they have become collectors items.
A recent post on MetaFilter has pointed out several sources for images of some of the labels, and other sources of information about the market for them as collectables.
There are more, with smaller images, on BlueSkySearch. The Crate Label Museum is most extensive, though the images are unfortunately small (note the dropdown at lower right to select categories, and note that many categories go on for several numbered pages).