Moral Event Horizon: For Zombies of the Gene Pool. In their youth, several of the Lanthanides had drunken sex with an underage female acquaintance at a convention; applies In-Universe as well, since the narration notes that Marion's tone of voice is a lot less respectful after The Reveal.
When Bimbos was first published in 1988, SF/fantasy, gaming, computers, and fandom in general were still extremely niche activities. It shows in the general attitudes of the non-fan characters (and perhaps even in the writer's).
Marion actually gets a mental monologue where she reflects on her own Values Dissonance, how in college she had the "Fans are Slans" mentality that non-geeks weren't "real people", and how she realized how disturbing and selfish that attitude is once she grew out of her outsider phase.
