And you couldn't say something about it to her face when it was YOUR yardsale? You had to write to Hey You to confront her? I could see if you saw this at somebody else's yardsale. But it was YOUR yardsale. So SAY something to her. And loudly, with raucous humor, to call her out but while making everybody else laugh.
It's like people in SoCal seriously have no clue how to deal with people one-on-one anymore. They also don't know how to have humor and be funny to turn weird situations into ROFL moments. It was already this bad back when I lived there years ago. I see nothing has changed!