If NH/SS were to accept the B/S pairing now, then it just proves that they were there for the looks, and not a single kitten was given to their personalities or interactions. Everyone is just a kittening trophy.
Naruto: Who cares about his dreams, his happiness? Hinata had always loved him so of course they should end up together. Naruto's feelings? Don't be ridiculous - it was just a crush. Who cares about his promises he made. Why should we be worried that the lifelong dream of the main character turned out to be so awful? He married Hinata - the lucky bastard.
Hinata: Personality - what's that? She was able to marry Naruto - she should be happy with that. Her personality or family doesn't matter. Her development? who cares if it regressed after part 1 - we're here for the boobs, and nothing else. Hyuuga heiress? We don't remember anyone like that. We only remember the Hyuuga princess.
Sakura: An independent character? What's that? She's always loved Sasuke - what's more romantic than that? Her friends don't matter. Her feelings don't matter. She's not happy? Don't be ridiculous - she married Sasuke. There's no reason for her to be unhappy. Naruto? Who cares if they would have been a wonderful couple - this isn't real life.
Sasuke: His personality, his actions. They don't matter. We have always been here for the looks and the angsty disposition. He's always perfect. So what if he's explicitly stated more than once that he's never loved Sakura. So what if they have tried to kill each other. They are a beautiful couple that's seen in every shoujo (we shall ignore that those pairs tended to have more development, mutual respect, and less skewering).