Intense competition and educational privatization have fostered demands for student personalization, leading to shadow education becoming entrenched in the Asian education sector. Its social influence is expanding and far-reaching, which has attracted many scholars to study this issue. Scholars have been arguing about the adverse effects of shadow education on widening the inequality of social problems, increasing students’ psychological pressures, and also the moral conflicts that teachers face. This position paper explores and discusses the rationality of shadow education from three dimensions: social, psychological, and economic. It argues that shadow education should exist as a co-curricular or supplement to formal mainstream education because it serves as a mirror that can reflect the missing parts of formal education, as shadow education can assist lower academic performing students and cater to need-oriented functions under-utilized within mainstream education. This article concludes with some recommendations for education policymakers in the Thailand Ministry of Education (MOE) in Thailand regarding the rising of the shadow education phenomenon. With stronger oversight of shadow education operators, improved communication between mainstream schools and parents, and increased financial support to the public education sector, a dynamic synergy between mainstream schools, shadow education operators, parents and students can be achieved.