Shortages intensify scrutiny of resource-allocation practices in healthcare settings. Although evaluators ostensibly value striving and hard work as rationing criteria, in actual resource allocation choices in a large-scale field study of 268,679 medical crowdfunding campaigns and in three experiments, we find that candidates perceived to be more “naturally” advantaged are deemed more deserving of healthcare resources than hard-working “strivers.” We observe a preference for naturalness in resource-allocation decisions across a wide range of situations and types of resources, including medications, hospital equipment, and financial support. This documented preference for naturalness has important implications for contexts plagued by shortages and rationing. We discuss practical mechanisms that could help debias decision-making processes and new strategies for addressing the psychological, health, and moral consequences of resource allocation under scarcity.