The cartoon was intended to be an exercise in silliness. While I have never met a cow who could make tools, I felt sure that if I did, they (the tools) would lack something in sophistication and resemble the sorry specimens shown in this cartoon. I regret that my fondness for cows, combined with an overactive imagination, may have carried me beyond what is comprehensible to the average Far Side reader.
https://en.wikipedia.org/wiki/Cow_tools
Guess I’m not the only one who didn’t get it