[simias]

>The wallet app I use is the very definition of simplicity

Simpler and more convenient than Visa? What if I buy something online and the other party scams me by not delivering the goods?

There's more to the economy as a distributed ledger. If bitcoin was to replace fiat entirely it'd still need 3rd parties to settle disputes, provide insurance, distribute the risks etc... In other word banks, or "central storage with insurance" as you prefer to call them.

The cost of the PoW algorithm is on top of all of that, not an alternative to it. It's not the problem it's solving.

PoW is there to solve the "distributed ledger without trust" issue. Except that if you end up having to trust your bitcoins to a "central storage with insurance" anyway I'm not sure I see the added value over the current solution.