Well, if you fear any animosity then I'd not apply my stick directly to the car and make something where you could just place it in the rear half window and remove it when your not driving so that way your not "one of those."
Here in Arizona they passed a bill to let hybrids have alternative fuel registration, which was a special license plate rather than a sticker and ~95% discount on registration. It was of course pending federal approval which was denied, but they issued some plates illegally for a few weeks there (I still see you out there once in a while, I'm turning you all in) and I tried to get one only to get a big NO. But I had it all planned out how I'd have a quick disconnect for my plate to avoid any car damage while parked. The reason there is a general dislike for alternative fuel vehicles here is because prior to all this the state passed a good intentioned tax credit for alternative fuel vehicles that went terribly wrong. People were getting $20K rebates to buy Escalades with a half gallon propane tank, which would run mainly on gasoline and still get the HOV lane access. A friend with an electric truck had it keyed while it was parked plugged in to a charging station (they didn't get any rebates on it).
Now I doubt you'd have anything near that level of trouble, but it's a thought. But I agree, don't do 55 down the HOV lane.