There is also an idea that single yellows 'don't really count'. In my small town there is ample parking, but there is one spot with single yellows and clear 'No parking 8-6' signs, in an area where people need to be able to turn and pass each other. But about 50% of the population seem to feel that this is some sort of 'Oh, look, a special clear space just for me!' area. I have taken to tapping on windows and saying as charmingly as possible (not very) 'Do you ever wonder why this area is so clearly market as 'no parking'?'