I was contacted by Cher, the owner of the store, regarding my first experience. She was apologetic and pledged to fix the issues I encountered on my initial visit.
When I revisited the store today, she gave me some samples of their 72 and 91 percent chocolate, and some truffles as well. I saw that she had indeed added signs to indicate what was in stock, and told me she spoke with her employee about how to offer better customer service. I'm impressed by her follow-up -- 3 cheers for businesses that adapt and make themselves better!