Why is it fashionable to dress like I'm from Paris, but stupid and laughable to talk as if I'm from Paris?

If I suddenly wake up tomorrow and start talking with an accent from France, Germany, Russia, or anywhere else I'll be a fake and a poser. However, if go shopping a drop a wad of cash on clothes that make me appear to be from those places, I'm suddenly fashionable. To me they seem to be the same thing.