Yes, I once had an encounter with a celebrity without initially realizing their status. It happened at a hotel lobby when I was attending a conference. A friendly person struck up a conversation with me about the event and general topics like travel and leisure activities. They were dressed casually, without an entourage, which made them blend seamlessly into the crowd. Our conversation was relaxed and engaging, without any hint of their celebrity status.
The realization of who I was talking to came when another guest approached us, excitedly asking for a picture. It was then that the person I was talking to kindly obliged, and it clicked in my mind that they were indeed famous. Upon overhearing their name mentioned during the photo interaction, I was able to look them up afterward and confirmed their prominent career in television. It was an unexpected surprise, turning a random conversation into a memorable encounter.