I've had this discussion many a time on motorcycle helmets. They range from $50 and can easily get over $1000. I strongly believe you hit a threshold for safety at a certain point (~$180) and you're paying for non-safety items beyond that. Comfort, aerodynamics (noise), weight and, most obvious, style/branding.
That being said: I generally pick a mid-range (~350-500) motorcycle helmet as many of the added items are worth my money but I'm of no illusion that safety is better than a $200 helmet.