... and that's relevant how?

I suppose you hope it's relevant because, "the solar power comes just when they need it the most" ?

They don't seem to do the math quite so happily, though. Maybe it's #1 and #2:

First, Safeway buys in very large lots from certified suppliers, who can commit to (almost) always having carrots.

Second, those suppliers have to deliver at a loading dock, and maybe at a central location, too.