The Sound of Someone Not Finishing Their Thought

I was talking to my new co-worker Erin about something that's been bugging me for a while. In The Sound of Music, during "Do-Re-Mi," Maria Von Trapp is trying to teach a group of kids (American actors with fake British accents playing Austrian children) how to sing. And at one point, she says, "Now, children, Do-Re-Mi-Fa-So, and so are only the tools we use to build a song." What the f, Maria Von Trapp? The only ones you left out were "la" and "ti." Would it really have taken so long to rattle off those two extra notes that you had to say, "and so" as if there were forty more notes instead of just two? That's just lazy, lady. That's just lazy.