The short answer is because the EU banned them.

The long answer is because they have a drastically increased chance of making you severely ill.

In Europe, eggs are not refrigerated, and when you buy them you can see that they are slightly shiny.

In the US, eggs are refrigerated, and they are matt (and, anecdotally, always seem to be perfectly white; though that’s a separate thing).

The reason US eggs are refrigerated and matt is because they go through a chemical and mechanical cleaning process before they hit the shelves. European eggs will sometime have a feather or piece of straw stuck to them, but Americans think that’s gross so American supermarkets insist the eggs are cleaned.

Edit: As if to prove my point, I got these this week from the supermarket.

/Edit

The problem is that the shiny surface I mentioned is a natural varnish which stops bacteria from penetrating the egg shell. Remember that eggs sit in the warm underneath their mother for weeks- they’d need to evolve a method of ensuring the egg can’t be infected. The varnish is that method.

Leave the varnish on and an egg can remain fresh for around a month without being refrigerated. But when you wash the eggs, you scrub the varnish off. Now bacteria can penetrate the shell, so now the eggs have to be refrigerated, otherwise they go bad.

The journey from the US to the EU is long, with plenty of opportunities to break the refrigeration chain, and the second that chain is broken the consumer is in danger. Just because the egg is refrigerated when you buy it doesn’t mean it’s been refrigerated every second all the way from the producer.

In the EU, it’s illegal to scrub eggs in a manner that removes the cuticle (the varnish). It’s also a legal requirement in many EU countries, and standard practice in even more, that chickens be vaccinated against salmonella, which is not required or widely done in the US.

So the EU banned them. Quite sensibly, in my opinion. I’d rather have straw on my eggs than food poisoning.

EDIT:
I appreciate all the attention this post has received, but despite my comment below I’m still getting a lot of edit suggestions attempting to correct something which is not actually a mistake- in British English, we really do spell it ‘matt’, without an ‘e’.

Edit 2:
I’ve had to have the same conversation repeatedly in the comments, so just posting this here:

• The US reports higher rates of illness from foodborne illness than in the UK. Annually, 14.7% (48m) of the US population suffer from an illness, versus 1.5% (1m) in the UK. This is nearly ten times the percentage of population.
• The US reports higher rates of deaths from foodborne illness than in the UK. The annual death rate in the US is 3,000 per annum, versus 500 in the UK. [The US population is about 5 times the size of the UK.]
• The US Centers for Disease Control and Prevention report around 380 deaths in the US each year attributed to foodborne salmonella poisoning. The most recent epidemiological lab data from Public Health England, 2006 to 2015 shows no deaths in England and Wales from salmonella…
• The Food Standards Agency recently updated its guidance to say that eating soft-boiled British Lion Mark eggs is now safe, thanks to a dramatic reduction in the presence of salmonella. By contrast, the US Food and Drug Administration still advises US consumers to hard boil their eggs due to salmonella fears. They report 79,000 cases of illness and 30 deaths a year from salmonella infected eggs.

If you’re here to argue that US eggs are no more dangerous than UK eggs then please bugger off. They are; this is a plain and simple fact.

Disclaimer:

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