I don't think it has anything to do with how much discussion there was - the majority of our users don't even visit this meta site.
Instead, I think it's because it's rare to see an
identify-this-game question that meets the requirements, so when we see one we upvote it, sort of like rewarding good behavior.
And sometimes the game looks good, which makes me want to find the game as well.
And then of course, people just love trivia. On the Sci-fi and MoviesMovies Stackexchanges, identification questions are allowed without strict rules, but they also get an unusually large number of votes.