> Civilizations and cultures across time and space all stress that what really makes people happy rarely involves material well being

Well, the texts that survive those cultures stress that. But historically reading and writing were highly controlled political activities. So you should probably consider the political motivation behind those texts. The good life for a peasant farmer in the dark ages would almost certainly involve the accumulation of modest surpluses to be traded for quality of life enhancing material goods. But you can bet your cart horse on the fact that the texts which were being produced by the state - and delivered to the farmer in mandatory weekly Mass - strongly encouraged the redirection of that surplus to the state in the form of tithe or similar in exchange for ‘spiritual access’.