> keep their eggs in the coolers

This is down to a very specific thing that happens in the USA and doesn't tend to happen here. If you wash an egg (because it has feathers or looks a little "dirty") you remove a sort of protective membrane[0] on the shell's surface which leaves it open to infection. To prevent this you need to refridgerate the eggs.

That said, we do refridgerate eggs in the EU. Every supermarket I've seen in UK and Czech Republic does this, and everyone I know puts their eggs in the fridge when they take them home. It may not be necessary, but we do it nonetheless.

[0] https://www.npr.org/sections/thesalt/2014/09/11/336330502/wh...

edit: I am now remembering some shops that do have them outside of the refridgerator :D