“Many luxuries are culture-specific. They are desired within a culture but not without. Group selection has no way to eliminate the growth of such luxuries because migration never responds to the difference of consumption in these items. Therefore, a distinction should be made between “universal luxury” and “provincial luxury”. Universal luxuries are desired by all human beings; provincial luxuries, only by a group of people. Group selection suppresses universal luxuries, but leaves provincial luxuries free to grow. This explains why culture was so diverse across pre-industrial societies despite the monotony of life (measured by universal luxury).”