The Boise library that we go to sometimes has a parking area near the door with signs saying those parking spaces are for Fuel Efficient Cars. It seems kind of silly to me, the parking lot is often almost full, but not full. If more parking was needed there is a shopping mall nearby. I think instead they should promote walking to the library as several houses and apartments are within walking distance. All the parking spaces have about the same walk to the front door of the library.
Today I had to laugh because one of those Fuel Efficient spots had a big old boat of a car-I would guess the car was made in the 70's. Add to that the bumper sticker had something not nice to say about Prius owners. If I had a better phone I would have taken a picture.