Lots of things don't make sense financially. I spent probably 15K in restoration of a 63 Nova (not an SS) for my wife. I'll never get that money back out of that car, but I didn't buy it as a financial investment.
I didn't buy my diesel or my TT as a financial investment either. I'll probably sell my TT and buy a 5er in a couple of years, and that won't make financial sense either.
I don't care... Im at a point in my life where if I want it, I buy it, and I don't care if it is smart financially or not. I enjoy towing with my diesel, so to me, it's worth it.
Mike