Spamming Users Of Android With Notifications

Recent versions of Android (KitKat) have the ability to turn off notifications on a per-app basis. It is a commendable feature.

However, some apps like Domino's Pizza (India), Flipkart and Flipkart eBooks are able to routinely override this setting and bug me with notifications.

l don't know what loophole these apps found in the Android operating system, and how can they override explicit setting by me (in a non-rooted phone), but it is a nuisance.