[I know I talk a lot about food, but what do you expect from a cook?]
Eggs are not refrigerated here. Yep. Here they are sitting on my counter.
As you browse through the grocery store and eggs are on the shelf in the egg aisle. Matt was a bit freaked out by this, but he discovered the explanation—Americans have to refrigerate their eggs because we wash them after they are laid.
Eggs have a natural protective coating on the eggshell that keeps the egg inside stable preserving water and oxygen while it prevents bacteria from getting into the egg. Washing this coating off results in the eggshell being compromised and any tiny crack can let in bacteria. So once washed, they have to be refrigerated to keep them safe to eat. The U.S. is actually one of a a handful of countries that washes eggs. Imagine that. We are the paranoid ones on this.
The eggs are washed because of a fear of salmonella. Salmonella can be passed from the hen to the egg while the egg is forming and people have been sickened from salmonella infected eggs. This is why they tell us not to eat raw eggs. Washing the egg is meant to clean way any potential salmonella. But the salmonella is inside the egg, so why bother? Aesthetics of course. No one wants to see a dirty egg.
In countries where they do not wash eggs, they either vaccinate the hens keeping the egg salmonella free or, in the case of New Zealand, being an island, there is no salmonella. (There was one outbreak that they quickly addressed. The theory is that is arrived by an infected human or bird.) So I am free to eat raw eggs here if I want and I will not have to worry about salmonella.
If the hen has not been vaccinated, and in the U.S. we do not vaccinate, due to its cost and complexity (of course it is all about cost) then there is still the chance of being exposed, egg washing or not because the salmonella is already in the egg or the eggshell has been compromised somehow.
A really good story on this can be found here.
A Yank Among the Kiwis 