Why hasn't a car company developed a power sunshade for windshields?

It could run on a track on both sides of the windshield, and be activated by a switch like power windows or a convertible top, and function only when the car is in park. I think it would be a no brainier to at least offer it as an option. Do maybe RV's have these? anyone?

 

They have them on the rear window on the Taurus, but thats to keep sun out while driving not while parked, and a front one would only be for parking so im guessing they figure with remote starts and nice A/C and cooled seats and stuff on these it wont be hot long while you drive and dont really want to put money into something that isn't used in every climate and isn't useful when using the car.

 

Because the 1 time it mistakenly goes up while driving (through whatever sorcery) it will lead to huge settlement and withdrawn from the car manufacture.