Still deserves a WTF, because that shit is creepy as F. There's something wrong if even one farmer did.
I'm going to guess that maybe kids dared each other to do it. I doubt that any farmer did.
Having known a couple of farmers, I'm pretty sure that at least a few of them did it as a joke. Like sending the new guy out to pick up some doughnut holes.
Off-topic, but we used to get doughnut holes. Basically, little pastries made exactly like doughnuts but spherical and about the side of the hole in the middle of a doughnut. They really are a thing, or were when I was a kid. I have not eaten a doughnut since I worked at the homeless shelter where we got donated stale bakery goods. Not yet spoiled, but very disappointing to bite into. The doughnuts looked just like the fresh ones, but yuck! they put me off doughnuts forever.