I've met dozens & dozens of celebrities, and lots of US politicians from Presidents & Cabinet members, Governors, Senators, etc, and senior military up to 4-star.
My most recent celebrity meetings were a week ago in Fort Lauderdale, with Sharon Gless and George Takei. She was in the TV crime show Cagney & Lacey, and later played Michael's mother in the US version of QAF. Takei was the navigator Mr. Sulu in the original Star Trek TV series, and later the movies.
Gless was presenting Takei with the "National Valuing Our Families Award" for his advocacy of gay families. I talked with them both afterwards, and also with Takei's husband, Brad Altman, who shared the award. (Together 22 years, they were legally married in California 6 months ago, that marriage now in peril while a ruling from the State Supreme Court is pending)
My partner's favorite celebrity story is meeting Judy Garland in 1969, when she dropped into a gay bar in Boston, just a few months before her death. She was very charming & funny, and sang impromptu at the piano. Then the patrons sang with her, and later by themselves to her, and my partner said it was magical, right out of a movie.