That brings up an interesting thought. Is the energy (cost) being expended actually going somewhere? I think perhaps, the fact that people put some sort of valu

That brings up an interesting thought. Is the energy (cost) being expended actually going somewhere? I think perhaps, the fact that people put some sort of value onto teach of the transaction, no matter how minimal, accurately (though maybe not precisely) models the "stake". You wouldn't think much on using RSA keys as a public ledger, but as soon as you are tracking something that has some nominal, perceived value, people treat it with more respect and accountability. (Now, is this inherently true? I don't know.)