Although eggs are displayed on a (non-refrigerated) shelf in UK supermarkets, if you look at the egg carton, they all state the eggs should be refrigerated after purchase.

Presumably this is because eggs stay fresher longer in a cool environment and keeping them in the fridge is the easiest way to do this if you don't have some other cool storage space?

I would venture a guess that this is a case of “better safe than sorry”, although admittedly I don't know what the exact verbiage on an UK egg carton is.

Some supermarkets may decide to refrigerate the eggs, even if it is unnecessary. The shell of a cold egg will get wet when it warms up (condensation), and bacteria on the shell will thrive. This could lead to dangerous levels of contamination on the shell, and some of it might make it's way in your body.

I live in Cyprus where the current temperature is 38c and eggs are not being sold refrigerated but we dorefrigerate them at home to extend their lifetime.

As far as I know, in Denmark, eggs are produced unwashed and salmonella free. Supermarkets (unnecessarily) refrigerate them because customers expect that.

Also true in Norway and Sweden. The funniest part is that IIRC, the "best before" date is based on storage at room temperature, due to EU regulations, but everyone in the Nordic countries keeps them refrigerated.

But I thought Denmark had more of an issue with egg salmonella than Sweden and Norway? I've seen Danish cooking shows where they take care to use pasteurised eggs/yolks whenever they're not cooked in a recipe (like for mayonnaise), but never in Norway or Sweden.

In Finland, some stores might stash eggs in refridgerated sections but overwhelmingly they're kept in room temperature. Salmonella is virtually non-existent in Finland. Eggs can generally be consumed even raw. That is because of a special stricter-than-usual control of poultry and egg production which effectively means that only Swedish and Danish eggs meet the import standards. Yet no eggs are imported to Finland anyway and the country is actually a net exporter.

Plenty of eggs are sold in room temperature in both Norway and Sweden. And neither country utilizes refrigerated transports, so there is no unbroken cold chain.

Isn't there natural refrigeration in those countries most of the year?

You can't put eggs outside in winter, frozen eggs crack