There were haters of Shukla, Rubina, Gauahar as well even if they were winners of their respective seasons. Being a winner doesn't mean you won't have any hater and Shamita Shetty is yet to be a winner despite playing the game for the third time.
I personally don't like her because she's arrogant and acts like she's better than others. Although I would agree most of my dislike is based on OTT. On top of that the special privileges she gets from Bigg Boss would get on anyone's nerves who don't consider her a queen.
But I don't see her getting anymore hate than any other contestant. Why are her fans expecting her to not get hate or be bashed? She might be getting special treatment inside the house but outside the house she would be treated like a regular contestant.