I think taking sides results from the following sequence: the original poster posts something, different posters present different and conflicting opinions, then someone or more than one "Thanks" some of the these views. For me personally, I prefer people to quote the person they agree with, and add their own personal reasons. I don't mind different opinions. But using the "Thanks" button is perceived negatively if it is clearly not used uniformly. Usually only the original poster shows his/her appreciation to all replies.