That’s odd - we find double-yolked chicken eggs all the time, twice in one week recently. I doubt they check to know that they are double in the first place.
Why can’t they sell double turkey eggs?
Because they aren’t uniform or something. This was the law back in the 60s. That’s why you don’t find double yolks in store bought eggs. The farmer’s kids would candle each of them before packing to ship out. Candle meaning hold up to a light to see inside. That was their livelihood so it was an endless chore.