@vandacca,
it IS necessary.
Maybe one cannot look directly into the luggage compartment through rear or side windows without the aid of sunlight or flashlight, but with those aids you most definitely can.
With the 6/7 seaters there's a free view through the windshield into the back - with the 5 seater this is not the case, and this is one of the reasons why we waited for it.
It's also an issue of not having the content of the luggage compartment immediately visible to passengers, and having less room to heat in winter.
In many parts of Europe leaving any items visible inside a parked vehicle is not wise, and having to stow everything away in the underfloor compartments is not practical in everyday life.
A vehicle in this price range should be reasonably equipped - we're talking about a "premium" vehicle, not some discount Dacia (which BTW does have such a shelf).