Eliminates the hastle of trying to load a sheet of film at a time while sticking your hands and arms in some tent like contraption. The pre-loaded film packs also eliminate the possibility of getting dust or other contaminants on the film during loading. If you are shooting transparency film and having it processed by a pro lab it is easier to shoot and mail the film pack than go through all the hastles of unloading the film holders and packaging the film for shiping to your lab.