That's a good reason to have a AWD sticker. For me it was the chain controls in the Sierra mountains. When you head up to the mountains to go skiing, they make you put chains on your car if it's snowing. (California drivers suck in the snow and should have chains around their hands so they can't drive at all when it snows. But that's just my opinion.)
Anyway, 4x4 and AWD cars are exempt from chain controls. I got tired of arguing with the guy about my car being AWD, so I had the decals made up. Works like a charm. I had some extras made up, but gave the rest away at the Reno meet.
Matt