Education and development are essentially the most 'durable' of goods - it cannot be stolen once taken - only damaged or destroyed by killing the bearer. In the past nutrition also played a similar role where better nourished aristocrats would have a concrete advantage over peasants.
With no cataclysms to prove their ability to rebuild if needed, wealth's ability to self perpetuate means ascribing it to stability makes sense. Since they would remain wealthy as both with and without the 'virtues' (in the sense of self-promotion as opposed to morality) its presence is irrelevant. All they need to do is avoid doing anything extraordinarily stupid and wasteful.
With no cataclysms to prove their ability to rebuild if needed, wealth's ability to self perpetuate means ascribing it to stability makes sense. Since they would remain wealthy as both with and without the 'virtues' (in the sense of self-promotion as opposed to morality) its presence is irrelevant. All they need to do is avoid doing anything extraordinarily stupid and wasteful.