"But God said to him, ‘Fool! This night your soul will be required of you; then whose will those things be which you have provided?’"

Miserliness and dissipation have always been problems. Harder money doesn't solve this, instead it protects balanced people from the effects of others' greed and spending.

The two extremes you mention don't exist. You'd have to be a selfish monk to save only and never spend. And someone in an economy with hard money can always work his way to savings (unless something else holds him back).

I don't really think this is a technological question, bitcoin is a restoration of gold, the main difference being that it makes it easy to transact large amounts without giving up custody. This could have negative implications, but is I think orthogonal to people's desire to be economic actors.