I have heard that too, but there is some hope. I caught Spot (White Rock +? barn yard mutt) eating an egg one day and called my mother in distress. "Maybe it just happened to be broken and this was an egg-eating of opportunity?" Mom suggested. No need to jump to conclusions unless it happens more than once.
For the next couple of days, be very vigilant about collecting eggs. Make sure you hens are not lacking for food and water. You might even pull out some sort of treat and feed them away from the nest box. Take away the opportunity to be "bad" and distract them as much as possible. I hope that works for you.
At my mother's house, they had a bad thunderstorm back in early July. One of their Red Star hens apparently died of heart failure during the storm. She was over two years old. Then Mom noticed they were getting more eggs each day. The collected eggs didn't have slime (broken egg) on them. AND the rooster's comb started to heal ("someone" had been picking on his comb)! The now-deceased Red Star was an egg eater! Needless to say, my mother and my brother are no longer upset that a hen died. Add to it that Miss Egg Eater had apparently been consuming 5 or 6 eggs per day (the amount of the "increase") and they are almost happy the hen is gone.
