Because sometimes you want to bring your 1946 Kodak Brownie box camera on a backpacking trip to take a photo of your wife in front of a slot canyon spring in the Arizona wilderness even though the camera's Six-20 film was discontinued in 1955 so you jam a 35mm can in there and then have to take two identical photos on top of each other to allow enough shady light in since it has no shutter settings and then scan the photo in yourself after developing.