It's a normal behavior and will pass when egg shells firm up and no longer get damaged in the nest. No need to try and "break" the culprit or cull the bird. This too shall pass. Have had chickens for 38 yrs and never had an "egg eater"...they will all eat eggs opportunistically when they are cracked or broken open. It's important that they do to keep the nests clean..it's instinctive.
I totally agree that they eat cracked eggs opportunistically, as I have seen this myself, without it developing into pecking open normal eggs. But occasionally they do learn to peck open firmly shelled eggs, and begin eating them regularly. Enough people have seen this happen, so I think it's undeniable.