^ ever heard of Road-Side Assistance?
Seriously though, I'm sure there is a level indicator just as there is for fuel, if you run out how is it any more BMW's fault than if you had run the car out of fuel?
-- 2015 i01 (i3) with REx, Laurel Grey, all options, 24 month test drive.
-- 2003 330i ZHP, Imola Red Build Date 03/03/03 SOLD! Owned for nearly 9 years.