The only time it ever happened was once in the 70s. A guy bought pixy stix, opened them up, laced the candy with cyanide, closed them with a stapler so they were clearly adulterated, and then gave the candy to his children and a few of their friends. His intention was to murder his children to collect life insurance because he was over 100k in debt. His son ate the candy and died. He died quickly and his death was linked to the candy quickly enough that police recovered the other adultered candy before another other children died

He was fairly quickly identified as a suspect and then caught. Somehow over the years this story of a shithead scumbag father murdering his child morphed into the idea that a stranger would adulterate candy for the fun of it, which as far as I am aware has never happened. Unless the original poster isn’t lying which would likely be able to be substantiated fairly easily as they clearly knew which house gave out the apples so the perpetrator would be easily identified. Or maybe we’re supposed to believe they found a razor in their children’s candy and just let it go without reporting anything to the police or media, who would obviously pounce on the one time in history this urban legend finally came true aside from a sociopath father trying to pull insurance fraud.

https://en.m.wikipedia.org/wiki/Ronald_Clark_O%27Bryan