For some reason I just can't imagine that a passenger vehicle was
designed to carry more than half it's own weight in books, bricks,
cement, rocks, whatever.

And it isn't classifeid as a half ton truck.
(I do know that half ton trucks are speced heavier than a Vanagon in the
frame rails and suspension alone, and I'm not even thinking about the
engine yet)

No negative vibes, just using some good ole fashioned common sense.