That's more than 'a little' unsportsmanlike. It's complete BS.
This is the kind of thing you see when two 7 year old kids are playing.
This should never be tolerated.
I can understand the chair umpire perhaps not seeing it as it happens. But if Goodall is commenting on it, it means that it has come to the attention of people in tennis. As such, someone definitely needs to talk to her NOW about this, and tell her that if she does it again, she will be punished.
I just wish that the rules would allow a more severe punishment than losing the point. After telling her not to do it again, I'd like the powers that be to be able to suspend her for a month if she does it again. Because this crap has NO place in the game.