It really is nice how obviously fond Elphaba is of Glinda right off the bat in the movie, with What Is This Feeling showcasing how much Elphaba enjoys their little feud. For the first time in her life, someone's judging her for her, rather than her skin or her magic. Glinda doesn't give a shit that she's green, she's mad that Elphaba's taste in clothes and decor clash so severely with her own! She doesn't care that Elphaba could accidentally kill her if she got too angry, she's too busy being upset that Elphaba keeps minorly inconveniencing her! How refreshing that would be, to meet the most annoying person in the world and discover that her own narcissism has caused her to be the only person who sees you for who you really are. Of course Elphaba would take the hat seriously as a gift -- has anyone other than Dulciebear ever gifted her anything? Of course she would gamble her own self-confidence at the Ozdust -- at worst, Glinda's ego is so massive that she would never allow her mortal enemy to be the butt of someone else's joke. And in the best case, well, Glinda recognizes how important she is to the one person that she knows has no one. The only one who gets her, the only one who has ever understood her, standoffish and rude the way a stray cat is before it finally follows you indoors.
It's a real shame this story couldn't be anything other than a tragedy, huh?