Well actually, I don't think you are missing a thing. As I recall, Wild Bill carried two - just in case he needed a Neu Yawk reload (lololol). As you know, these things were used for trail guns for many years until cartridge conversions, and later cartridge gun came along.
Nice thing is they are fairly lightweight, especially in something like the Sheriff's models or storekeepers models, and I wouldn't want to get hit with a roundball when I'm out in the woods miles from a hosptial, or anywhere.
I often think about one of the 1873 reproductions as a trail gun. Mikey.