Why do people have hangups about eating organ meat?

It's amazing how we don't appreciate out kill in America. At the rate we consume, we plow through everything like vampires. We eat meat, yet most of us only devour the animal's flesh. Lots of people have an immense stigma towards organ meats. Through my extensives studies in anthropology, I admire the way several indigenous groups eat every part of the animal. I'm curious to know why we don't do that as much in the industrialized world. If it were up to me, all meat would be cut into fine strips or grinded together into sausages. Every part of the animal would be included, nonetheless. The only parts left out would be the bones.