With the infusion of advanced technology, interactions between customers and firms’ representatives take place in brick-and-mortar stores, 2D online sites, and even 3D metaverse environments. In the metaverse, a firm’s sales avatars interact with other users while representing the firm, recommend, and sell virtual items. Previous literature about the effectiveness of sales representatives agrees that a firm representatives’ smiling faces engender customer satisfaction and better interactions. However, it is unclear whether smiling faces of sales avatars will work the same way in the metaverse as they do in the real world. The current research examines whether a firm’s sales avatars with sad facial expression (vs. those with smiling facial expression) stimulate higher user intentions to interact with firm representative avatars, to purchase virtual items from the representative avatars, and to spread positive WOM about their experience in the metaverse. Moreover, focusing on subcultural appeal, we investigate why this unconventional phenomenon happens in the metaverse unlike in real world. We conducted two experiments to manipulate a firm representative avatar’s facial expression (smiling vs. sad) in the metaverse. We newly designed a metaverse place, and participants who put on a virtual reality headset are exposed to either a hat (Experiment 1) or shoes (Experiment 2) store where they can purchase a virtual hat or shoes. Experiments 1 and 2 basically tested the same things repeatedly. However, to improve internal validity and generalizability, Experiment 2 used human-like sales avatars instead of cartoon character-like sales avatars in Experiment 1, changed virtual stores from a hat store to shoes store, and finally controlled for various extraneous variables such as attractiveness, warmth, and competence of sales avatars, and user’s previous experience about metaverse. Sales representatives with a smile are believed to contribute to beneficial consumers’ attitudes and behaviors in offline stores. However, our experiments demonstrate that this well-received belief does not necessarily apply in the metaverse, where subcultural appeal plays a more critical role. In the metaverse, users evaluate sales avatars with sad facial expression (vs. with smiling facial expression) as more unique and cool (i.e., higher subcultural appeal), leading to their higher intention to interact with the sad sales avatar, to purchase a virtual item, and to spread positive WOM about their experiences. Our results imply that previous findings supported in the offline or 2D online sites may not work the same way in the 3D metaverse.