They unscrew. But, they are threaded really deep, and there is a rubber grommet on the door panel that gets in the way, so as you are unscrewing them, you will have to pull up. It helps to have a small piece of leather or something to grab them with.
Yeah, they probably are "just regular O-rings," but I had 1,000 of 'em. I had seen a post from a guy in New York who had put O-rings on his locks, and I liked the look, so I ran down to my local Ace Hardware and bought 12 O-rings for something like $0.83 apiece, individually shrink-wrapped.
Later on, I got to wondering about economies of scale and went online. I found that I could get 1,000 O-rings for not much more than I paid for the original dozen. So, for the hell of it, I did. Now I pass them out to other LX owners at M&G's (most notably, Starved Rock this year).
If chargerforums.com were a criminal enterprise, I guess I'd be known as "Paulie O-rings."