The attitude of the staff might not be excused as they are still expected to be courteous and polite with the guests (however, the way we feel about one's attitude is subjective so it's hard to tell how "rude" anyone is but the person who experienced it).
However, we, as Le Club Accorhotels members, know well that statuses are not recognized at Novotels (or Ibis) and yes, this loyalty programme is one of the poorest within the big chains but guys, we become members and we accept their rules. You know that you won't get late check-out due to your Plat status but of course it never hurts to ask nicely, as you never know, you might get lucky sometimes. But trying to argue or flash one's Plat card or status will honestly not help. No recognitions = no recognitions. If you get something, fine, be grateful, if not, then so be it, since it's stated in the T&C.
So why waste time and energy at these properties? Pick a Sofitel, Pullman or M-Gallery if you really want recognition