There are all kinds of reasons. Medical school cadavers for practice, Bones to be used in some surgeries (after sterilizing), various products testing, help with creating new medical equipment (think joints), and even research for forensics experts. There are actually body farms where they put corpses above or slightly below ground to study decomposition, and things like when certain insects show up or other stuff like pollen contamination. I saw that same story and it piqued my interest until I asked myself the same question. Hell - we probably get bodies from all over the world so we can test/research different races or ethnicities as well. USA has a ton of universities and medical corps that would certainly need this.