GONE ARE THE DAYS IN WHICH GRACE DOESN'T KNOW WHO THE HULK IS!
No, seriously. She's been experiencing Moperville society for nearly a year, is friends with a bunch of geeks, nerds, and dorks, and has been working in a comic shop for months. Her pop culture knowledge may be well above average at this point with bonus perks granting her knowledge of obscure trivia and movie quotes.
Also, she can totally recite Spaceballs from memory (even if she wishes she couldn't).