Did that artificially-intelligent chatbot just crack a rude joke?

A software developer with PolyAI who was testing the system, asked about booking a table for himself and a Serbian friend. "Yes, we allow children at the restaurant," the voice bot replied, according to PolyAI founder Nikola Mrksic. Seemingly out of nowhere, the bot was trying make an obnoxious joke about people from Serbia. When it was asked about bringing a Polish friend, it replied, "Yes, but you can't bring your own booze." Mrksic, who is Serbian, admits that the system appeared to think people from Serbia were immature.