Sparse, representational backgrounds make an appearance in “Odor-Able Kitty” (released 1945), the cartoon where Chuck Jones and writer Tedd Pierce try out the idea of a romantic French Skunk a la Boyer (but without Boyer’s voice).
The third drawing is supposed to be of a rounded picket fence.
And here’s part of the background wherein we find the disgusted cat who gets revenge on his tormenters by turning himself into a skunk.
I can’t clip together the whole drawing because about 3/4s of the way through the pan, the light from the camera reflects off the glass plate covering the drawings.
There are no background credits on the cartoon, but I believe Bob Gribbroek was in the Jones unit at the time, working from layouts by Earl Klein.