> no benefit whatsoever
Clearly, the benefits for any energy consumption should be seen from the point of view of the consumer. They wouldn't do it if it were of no benefit.
It would be more fair for you to describe the distributed ledger clearing as of no value to you. Because it definitely has a value to some folks.
That said: some other cryptocoins do indeed provide a ledger like bitcoin, still decentralized and trustless, but without mining (and without block rewards).