Witness Harry and Hermione as of Friday eve: Note the detail (not all of which appears here). There's the obvious lightning bolt scar, the crazy gel-ed hair (for both of us, I suppose), Harry's got his Nimbus 2000 (in case someone hadn't read all the books and doesn't know of the more advanced broomstickery) and a wand for each of us. But Crookshanks is there also, Hermione is toting one of her favorite textbooks, and our wardrobe is consistent with the white button-up shirt and tie overlain by the grey v-neck and black unzipped robes that appear in the films. On closer inspection, you will see that we located a Gryffindor symbol on the web, printed it out, and since I could not find a safety pin at the apartment, I stitched the crest to the robes. And by "stitched" I mean I pulled out the needle and thread and SEWED.
I mention all of this to you because we managed to attend a Halloween party with 30-ish other people, NONE of which had ever read any of the books or seen ANY of the movies. I can't imagine that a collection of 30 people exist in any portion of the english-speaking world where this is even possible. So we had to continually explain who we were and nary a soul appreciated the detail of our wardrobes. No less than 10 people during the course of the evening made mention that "oh and you brought a cat!", to which I would reply, "It's Crookshanks", and receive this retort, "wow, you even named it"! It just about killed me that we had to constantly say who we were so people didn't think we were "students".
Oh, and to top it all off, everyone now thinks I'm this huge sci-fi and fantasy fan because I've read all the books and people keep trying to ask me about Star Trek.