Thanks for sharing your precious memory! 
Perhaps the chickens felt less stressed and hence, could lay better quality eggs 

cryotosensei

food_and_drinks

Life cycle of chickens

We had chickens for a long time in their coop giving us plenty of eggs all the time. Way better than store bought. One day instead of buying more feed, I let them roam around our property instead of buying more. The eggs got so much better. Like almost overnight. Not super relevant to your post, but it always amazes me when I think about it. 