(Some Uninteresting Thoughts On) The New Math

I was fiddling around on an insurance website, just to get a quick and dirty idea of how much it would cost me to insure a second car. Now I understand that these calculators aren't focused on giving you a precision quote. If I called up my insurance agent and he gave me the exact same price for my policy that the anonymous website gave me, I would be absolutely shocked and also pretty ticked off that all of the things that make me a good and responsible driver (at least as far as the actuarial tables are concerned) weren't being taken into account.

Well, this calculator has me stumped. If I purchased the new car and only insured it - whether I sold my truck or just gave it to the first person I saw on the street - the price it gave me is more than double what it would cost to insure them both. How on earth do they figure this? I would expect insuring them both to cost a little more than just one, not so extremely the other way around.

I could park my truck, never drive it again, and still save more than half on car insurance. How the heck does that work? If anyone can explain this to me, I'd love to hear.