Coming soon: Knights of Badassdom, in which fantasy LARPers have to stop a succubus accidentally summoned through a spellbook bought as a prop.
(Portrayals of gamers on screen skew heavily towards LARPers becase they have far more visual interest than people sitting around a table rolling dice. See any news report about a gaming convention for examples. See also cosplayers versus everyone else at Comic Con.)
Having genre savvy characters deal with genre threats (even to the point of the players playing themselves as PCs) is fairly common, because hey, we're genre savvy so it's easy to reflect in-character.
I never had gamers appear in The Watch House (even though Cambridge has a biannual RPG convention) but I did have references to authors drawing ideas from Buffyverse reality. I'm tempted to set a Doctor Who adventure in a parallel world where Doctor Who is a hit TV show...