A gentleman's agreement between a certain faction of econ-crypto-tinfoil-hat-botnet nerds to assign trade value to the wastage of increasingly large amounts of electricity.
They are working on a real problem though. Paypal kind of works, but isn't ideal.
To address from a different angle, the phenomenon where you say electricity is being "wasted" to produce a bitcoin is analogous to the creation of a US dollar. Not to the using of it or acquiring of it. You can buy and acquire a bitcoin fairly quickly and cheaply, CPU/electricity-wise. Much more so than if you had to "mine" it. Much like dollars. Much cheaper/easer/faster to "buy" a dollar than to construct one out of thin air. (A legal one, anyway.)