Prior research shows that consumers act in ways to avoid associating with conflicting social identities. However, it is unclear how such conflicting social identities influence the behaviors of service providers when interacting with consumers experiencing vulnerabilities, leading to potential marketplace discrimination. Additionally, research has yet to adequately identify what type of intervention strategy may be introduced in order to improve service quality when discrimination occurs. Across six studies, within the context of highly religious service providers or highly conservative service employees interacting with LGBTQIA + consumers, we demonstrate that the motivation to avoid being associated with undesirable social identities negatively influences their service quality toward these consumers experiencing vulnerabilities, leading to discrimination against such consumers. This occurs because of an increase in social identity threat perceptions associated with providing service to these consumers. We also identify an important boundary condition, such that this effect manifests when providing service that is high (vs. low) in identity relevance. Importantly, we provide evidence for a common identity intervention (i.e., focusing on the commonalities between actors) as a strategy that increases service quality and show its effectiveness across multiple contexts and using real businesses.