I wonder how many attendees way back when would've found it obnoxious that people who like those new video game things started going to "their" con.
Funny you say that, because back when I used to go to the anime ones, I didn't go for any of the anime stuff and got a hard from my friends about it. I only went because dealers there sold Nintendo/Mario merch that wasn't available here in the USA (except through Ebay or some weird website) and I'd cosplay as Super Mario. My friends would attend all the panels, go to the show screenings, and cosplay as anime characters.For me it was just fun to walk around and see all the people, take and get pictures taken, and of course there were a few people having Smash Bros. stations or some small videogame stuff.
I guess it wasn't as weird as probably going to a comic book convention and seeing video game characters used to be, but I do remember my friends arguing with me and teasing me for not wanting to sit through the panels or watch any of the shows.