Probably because the headlight washer-bottle, coming as a later option, had a bit more thought and feedback put into it!
Dipstick, or float?
I can see the point of a float with an indicator stick in it, but a dipstick - How does that work with water then? (Or do you have particularly colourful and sticky water in the US!).
Hmmm. Bruce - You sure it's not that funny long one marked "Oil"
