I hear this "household typically has 2 or more cars" argument all the time. It's crap. We have 4 old cars, one for each person. It's not like one could just have a short-range only car. What would they do when they needed to go somewhere far-ish and everyone else is at work? Mind you that yes, everyone works every day and so takes their car.
I'm sure that most households with more than 1 car don't just have that car sitting around until they need to take a long trip (which could be a weekly or more occurrence). If you own more than one car, it's usually because your using it regularly.
I can't wait until electric cars can really be practical, but the theoretical option to have an extra car for distance doesn't make them so