As I understand it (from an outsider's point of view) a lot of kosher practise actually is basically about food hygiene - seafood is still a superb way to get food poisoning, for example, and raw meat really should be absolutely kept away from pretty much everything else, especially in hot climates where you're likely to eat salad. Blood is a great medium for disease transmission, so I'm not entirely surprised bloody eggs come under both religious and scientific prohibitions :)