I believe it's to make them last longer. I dunno what it's like there but here in Australia people will buy eggs from the normal shelf and when you get home into the fridge.
How long do you think eggs would stay in the open environment in a farm?
Eggs confuse me
People are told not to eat them raw because of a risk of salmonella (??) but you hear all about people drinking raw eggs in their exercise regime, and when people make cakes with eggs and eat the batter....that's right. Eating a batter that has raw egg in it.