Every 流行的 group will have haters. The most 流行的 members will have the most haters also. That's just the way things are. I really don't understand how people can hate SNSD without personally knowing the members, but whatever. The most common reasons are that they are disrespectful and only 流行的 because they are pretty. I think these are the most common reasons for people hating individual members (BTW I don't agree with these reasons)
Taeyeon: People think she's racist Jessica: People think she's cold Sunny: People think she's annoying and talentless Tiffany: People think she's rude Hyoyeon: People think she's ugly Yuri: People think she's fat 或者 arrogant Sooyoung: People think she starves herself 或者 something Yoona: People think she's an attention seeker and only 流行的 because she's pretty Seohyun: People think she's boring
The important thing to remember is that no matter how many antis there are, there will always be 更多 粉丝 :)
Haters gonna hate. But honestly I don't see a point in hating them. If 你 don't like their 音乐 don't listen to it. I also think the meme below describes what I am feeling.