I know this thread is about celeb jerks, but I think all my celebrity experiences have been not-bad at worst. Most of mine are musicians.
1. Slayer: met them when I was in college or thereabouts, at a signing thing for Divine Intervention. Tom Araya said he loved my shirt; I should've gotten him to autograph it instead of the damn album flat. Friend of mine in the stage biz says they are incredibly nice guys, even downright pedestrian (mind-f: imagine Dave Lombardo in a cardigan and loafers, metalheads!)
2. Sascha Konietzko from KMFDM: I shook his hand at the bus door and told him 'that was a hell of a show' (after a show of theirs at Hammerjacks in Baltimore) - he clasped my hand with his other hand and gave me such a heartfelt 'thanks, that really means a lot' that I still think to this day that he was f-ing with me.
3. Victor Wooten, bassist extraordinaire: I just happened to run into him at a guitar shop one day - no appearance or anything that I know of, he was just playing around on some basses. I was very "wow, do you know who you are?!?"... He was very nice, as were his people. Years later I'd go on to own a Fodera Yin/Yang bass (his signature model) with his autograph in Sharpie on the headstock. Side note: wish I'd never had to sell that bass.
4. The Cult: I didn't so much meet them officially, but the same friend aforementioned was working a spotlight at House of Blues Orlando and I was hanging out with her. After the show they sort of recruited me to serve as security to the backstage door near the bus, and I got a couple nods and waves.
5. Duff "ace of cakes" Goldman: Met him at an appearance, poorly attended due to weather, so I got to chat with him for a good while (at the time I also made sculptural cakes, inspired by him and his kind, plus we both play bass). Great guy, but toward the end he had to go and I started being "that guy", which I am ashamed of doing.
6. Cindy Morgan (Yori, Lacey Underall): Met her at a game convention where a buddy and I had a booth. She was incredibly nice, not to mention she didn't age badly at all =0). She talked with my buddy extensively about Tron video games, as he's somewhat known in classic game circles. She signed a Yori photo from her booth, as well as a copy of Tron which I ran out and bought that night after we met, and brought to get signed the next day (Already had one copy of the movie, but the convention was far away from my home, so now I have two).
7. Kari Byron: Personable enough but super time-crunched, so she wasn't especially effervescent - she seemed marginally glad about my daughter wanting to become an engineer or scientist because of her and MB, but again, there was a line a mile long. Still, we got a pic of the three of us together.
Bonus obscurities:
- Took John Stabb (80s punk band Government Issue) to lunch at Taco Bell once.
- If anybody remembers Ollie North's secretary, Fawn Hall, well, my grandfather's second wife, after my grandmother passed, was Fawn's grandmother. Fawn's house was PF huge if I remember correctly.
So, wow, yeah, I don't think I have any jerk experiences.