Rear Wiper Arm Ripped Off

[pmckenny]

The rear wiper arm on my Murano was torn off today in a car wash. So I guess I have a couple questions:

Any one know if this is a common design issue?

How much is it typically to relace the arm (the plactic cracked and is not salvagable at all)?

Also, looking for support on this one, when you wash a car and they say "not responcible for damage" don't you think that standard OEM and factory parts (lets say, for example, THE WINDSHIELD) are not included in that exception? If their machine went crazy and knocked out a window, they'd be responsible, wouldn't they? Don't you think a wiper arm is essentially the same deal?

Kinda irritated about this...help would be good.