I remember cars being covered with them. I worked at my dad's car lot and it was one of my many my jobs to clean them off the bumpers etc!
Every college, military installation, big business, high school and many others all had parking permit stickers!!!!
Hue PITA to get some off. I remember using acetone, gasoline (dangerous - prob wouldn't do that now) and WD-40 a lot. Vinegar was used to clean the gunk off the glass - especially good for cigarette smoke funk!
Ray