But their competitors lock out the nav system also! Not all of them, but most.
German carmakers don't, and Acura/Honda. Thats it. Infiniti, Cadillac, Nissan, Lincoln, Chevrolet, Buick (all GM) all lockout the system the same way.
I'm sorry you've been unable to adapt to your system. But thats an issue with you.
A bumper sticker? How childish.