“If polyamory has entered its cultural adolescence, swinging is its elder cousin who has long outgrown the kids table at Thanksgiving. The swinger lifestyle is probably the most normalized form of non-monogamy with its own reality TV shows, all-inclusive resorts, and origin story lore that includes World War II Air Force pilots. And no, the upside-down pineapple thing was not a widespread supermarket swinger symbol, but, yes, at this point it’s become a cheeky, unofficial logo of the lifestyle.” https://mashable.com/article/guide-to-swinging