Centrists exist because they listen to alternative views and can empathize with those views even if they don’t quite agree with them or if they can’t decide between the pros and cons. But to an extremist on either side, it looks like they are stupid, weak, or possibly just bad people, because if they were smart, Good people, then the centrists would OBVIOUSLY agree with THEM, and then they wouldn’t be centrists. This lacking of empathy or inability to understand opposing viewpoints, and therefore assuming malice or evil as the motive of anyone not WITH them, is the hallmark of all extremists.

Oh yeah, also people hate centrists because they come across as smug. Sorry about that.