First of all, I'm not sure what kind of a ladies night would take place at a pottery studio unless a reenactment of that scene in Ghost were happening. So, this establishment clearly doesn't understand what ladies want, nor even how to spell the word ladies.
Also, I believe the word they are looking for is complimentary (a.k.a. free), not complementary, which means matching or enhancing something well.
Incidentally, my idea of a ladies night always involves drag queens.
Thanks to Don for finding this catastrophe in Eugene, Oregon, and posting it to the Apostrophe Catastrophes facebook group.