There are a handful of stories that all gamers have, and that we pass around, ritually, when meeting each other or inducting new gamers into the tribe. Dice superstitions, "how roleplaying changed my life," and "the worst game master/player ever" are all well known anywhere gamers are, and we all have our collections of memorable anecdotes and thrilling incidents, either from our own experience or borrowed from the collective pool.
This is so much true that I tend to think of these topics as clichés. Sure, I can write about how writing helped me get through high school and made me a better person, or the bizarre behavior of some Dungeon Master, or the funny things I do with my dice when I'm bored, but why? It's good to revisit those topics every so often, trade the details of each particular incident back and forth, but there's little of real consequence to be said on the subject.
So what's really interesting to me is how fascinating these stories can be to non-gamers. Every so often I'll go back to gaming when I'm writing something for a fiction or a non-fiction or a poetry class, since I have to generate a fair amount of material for those classes and gaming is a reliable subject for me, since I'm interested in it. Then we'll workshop the essay or the poem or whatever it is, and a bunch of non-gamers, people who have barely heard of D&D, will read it, and while not all of them care, there are always a few who are fascinated. They want to know more. Even if it's something simple; that old reliable story of the guys who "train" their dice, say. It's a window into the customs of our peculiar tribe.
Which, I suppose, explains why those stories keep getting passed around. Even though we've all heard them, or stories like them, a thousand times, it's a way to reaffirm our membership in that peculiar tribe. (And to reassure ourselves that, while we spend our Saturdays pretending to be elves, we're nowhere near as crazy as "that guy.") They're tokens of our various customs: why we game, the trials we've all survived in common, our shared talismans and paraphernalia.