Despite the historic examples of people having ice cream sundaes after committing such atrocities, the word “picnic” comes from a separate source. That said, there is an uncanny similarity between the lynching theory and the etymology of the word. Etymonline claims that the word picnic comes from the French word “piquenique,” which in turn might be a smashing together of “piquer” and “nique” or “to pick up a worthless thing.” The idea is that you pick at small nibbles at a picnic.