At the end Lauren runs over to Julius to hug him good bye, knocking his hat off. Then just a moment latter, it falls off of his head again, all during the same embrace.
Lauren, 19 or 20 minutes into the film, while precociously discussing Heidegger with her (latest) stepdad, says that his "stuff" is mostly "etymological." She undoubtedly was supposed to say "ontological," since ontology (a branch of metaphysics concerned with the nature and relations of being) was within Heidegger's oeuvre. Etymology (the history of a linguistic form such as a word), of course, makes no sense in this context.
(at around 51 mins) On the Champs-Elysees a pedestrian makes an obscene gesture to the camera.