I suppose a movie producer (and screenwriter) can be regarded as a celebrity, though usually not so well known or recognizable as actors or singers are. I was a pretty young guy. This happened in my mountain-valley region of British Columbia. I was invited to a Christmas party, and George Lucas was there with his girlfriend. Lucas had a hideaway property with a cabin nearby, and the party's host was an electrician (and, I think, had done some work for him). "Star Wars" had come out, I'd heard of it. But I'd been living in a cabin, without electricity, and was quite out of touch with newspapers & the media then.
George sat most of the evening in a comfy chair, quiet, smiling kindly, Next to him, his girlfriend had all the young kids sitting on the floor around her, absorbed in the Christmas stories she was telling.