Store eggs (around here anyway) are bought through local producers. They are "relatively" fresh like the guidelines above say. I would also think that the packaging date is the same day or next day at most after being laid. We are thinking in terms of a few days to get a dozen if we have a couple layers, but the big egg farms (BOO-HISS!) have thousands of hens. They are candled, graded, washed and have an antibacterial put on them.
So yes, they are fresher th an we think.
That being said, I work for Safeway and I never buy eggs there. Partly because I have my own, partly because of the inflated "Free Range" prices (gimmee a break. $4.59+ a dozen) and mostly because I like my eggs coming from chickens who live a freer life.