We ate those a lot when I was growing up - scrambled eggs with pork brains were a treat (believe it or not). Of course, back then nobody could even pronounce cholesterol, much less know what it did to you, and the labels didn't tell you how much you were consuming.
Once, back in the 70's I took a tour of the Smithfield Foods plant in Virginia and saw a person whose job was this: she sat in front of a conveyor belt. A hog's head would come down the conveyor, then a big blade split the head in two. She then would scoop the brains out of each half, and put them into a plastic tub. I always wished I could take kids who were going to drop out of high school and show them that job: "Here's the kind of job you can get with no education."