Doesn't quite work like that, once you've got the momentum adding extra weight doesn't have as big an impact on the fuel economy as you might imagine, this is something I learned converting a campervan. A person who understands the physics explained it to me in more detail, but I can say that not far from doubling the weight of the van probably took the fuel economy from 39mpg to 33mpg.
You ignore the fact that while the EV1 was a first generation experiment (with 270L of boot space as it happens), Toyota deemed it succesful enough to create a NIMH battery powered RAV4... and the only thing that stopped them selling it was getting sued by the oil company that owned the patents to NIMH battery technology. There was a waiting list of disappointed buyers.
Since the majority of trips are local commutes, that's an incredibly huge market you casually dismiss. The rise of the electric car now there is a viable battery that hasn't been patent encumbered demonstrates this.
You've ironically managed to throw a straw man into that paragraph, I doubt electric car advocates are promoting 2 car households. These days car sharing clubs are growing hugely, I'd personally think a far better and probably cost effective solution would be renting a car for long journeys, though this is more accessible in cities where I'd guess many people are within 10 mins walk of a club car. Though batteries can be charged quickly enough (30 mins) and the infrastructure is widespread enough these days that long trips increasingly shouldn't be an issue.