A robe plus a stick does not equal a costume. I haven’t seen the latest Harry Potter movie, but I’m pretty sure nobody in Gryffindor was wearing a SpongeBob T-shirt under their cloak. And I’m fairly certain what you are calling a “wand” is a little cardboard tube off one of those hangers you get back from the dry cleaner. I don’t care if you’re just 8 years old, dammit, if you can’t run with the wolves then get out of the pack.
That goes double for you guys. That’s a brown bathrobe — you’re not fooling anyone. Also, a very important note: Get a lightsaber, but not one with the blade extended. First off, your pink plastic tube doesn’t look like a real lightsaber blade, it looks like a Pixy Stix gone agonizingly wrong. Secondly, how often in the movies do you see Jedi just wandering around, sabers extended, ogling the massive-breasted Japanese dolls, poking random passersby in the eye? I admit that the prequels would be vastly improved by this, but that’s not the point.
Wired News: Condemning Comic-Con Costumes