I leave mine on, but modern computers running idle use so little energy that I'm not terribly concerned about it. Sure, every little bit adds up, but same can be said for wall wart power supplies, the clocks on coffee makers, microwaves, etc. I would like to see solar power production increase to where at least this parasitic load stuff is essentially covered by free energy, but we live in a ridiculous time where politics and old money trump common sense.

Re: the confidentiality vs. leasing argument -- I don't buy it. I've stacked up hardware covering half a datacenter floor that was used for DOD contracts. It goes to auction where the public can come in and take it home... (ahem) for a small fee. It's not that hard to develop and follow a policy of handling storage media appropriately. If you're concerned that "someone" will screw up that process, well.. that's an issue with staffing.