Somewhere in Ponyville, long ago, a now defunct candy factory was built, through generations it had passed, but not only did it carry on the candymaking skills, but a curse, too.
It was common, that back in the days of Lore, a mare or stallion’s eyes were to be removed, for that is where the curse was kept. Legends tell that the curse would take place in the form of a pony’s eyes, and at a very early age, fillies and colts had to be taken through various tests, and few survived.
Though this is not the case anymore, elder ponies would often tell these stories to their grandchildren, usually at Nightmare Night.
The long line of candymakers have since died out, but young ponies would still enter the factory, hoping to find something valuable, and trade it for bits.
The closest Ponyville can get to being a candymaker are the owners of Sugarcube Corner, namely, Mr. and Mrs. Cake, and Pinkie Pie, there are indeed rumors of their ancestors being the candymakers, but they, especially Pinkie, have never said anything about the rumor.