That video kind of skipped the entire part where it turns the meat and ingredients into sausage. Like "here's a pile of meat, now it's being twisted off into individual sausage."
They what now? Did you watch the video, its only a minute long.
@18 secs she is mincing meat then mixing with other ingredients then they fit the casing over the spout and pump the sausage through.
Well that's how American sausage is made.