Optimization approaches for planning and routing of humanitarian field operations have been studied intensively. Yet, their adoption in practice remains scant. This opinion paper argues that effectiveness increase realized by such approaches can be marginal due to triviality of planning problems, external constraints, and information losses. Cost increases, on the other hand, can be substantial. These include costs of implementation and use, data gathering, and mismatches with organizational cultures. Though such costs are a key concern for humanitarian organizations, OR/MS studies typically consider effectiveness measures only. We argue a paradigm shift towards cost?effectiveness maximization and increasing the strength of the presented evidence is needed and discuss corresponding future research needs.