I'm sure whatever the U.S. uses to clean the eggs is IN the eggs. Cleaning the shells makes them porous thus the reason we have to refrigerate our eggs.
Farm raised eggs taste different because of what they eat. They forage, eat worms, grass, etc. Store eggs come from commerical farms where they are fed crap grain and corn. Same difference from grass fed beef from a butcher to beef bought at your local grocery store.