Energy Saver

Here is my question?

I do maintenance for this this fast food chain. The corporate office is telling me that it would be more energy efficient to run the walk in freezers at 10F instead of the normal opperating temp of -10F. I have my head scratching on this one? Would this be more energy efficient to where this would cost less on the owners electric bill? The walk in freezers have nothing more than bread and cookies in them. No icecream or anything that needs a deep freeze.