This has nothing to do with how chickens are taken care of. Salmonella naturally occurs in chickens and is totally harmless to them. In the US, we wash our eggs, which eliminates the salmonella but requires the eggs be refrigerated for storage. In most of the EU, eggs are unwashed, but the chickens are vaccinated against salmonella. Washed eggs can be refrigerated and stored for almost 2 months, where unwashed eggs last about 3 weeks.
Plenty salmonella outbreaks related to eggs still happen in the EU also.
Bro, there are hundreds of egg-related salmonella outbreaks across Europe every year.