It is only HDFC bank currently which is excluding all its co-branded cards from all the sale offers it "sponsors" irrespective of whether they give rewards or cb. Only 3 cb cards (sbi cb card, axis fk, icici amazonpay) are the major ones in the segment & all of them got excluded for instant card discount in one way or another long before HDFC which started doing it since last year BBD sale on flipkart.