Personally, I tend to consider that of any kind of "Professional Activist" or protestor. Even those I tend to agree with.
Any time somebody devotes that much of their life into a single topic or interest, I question their sanity. I do not care if it is abortion, anti-abortion, starting wars, ending wars, increasing vaccination, ending vaccination, it does not matter. When an individual becomes so consumed that their entire life is about one thing, I tend to believe they have lost touch with reality.
And yes, I do recognize more moderate ones. Like say MADD, which for decades has championed tougher laws against drunk driving. However, they have not gone over the deep end and attempted to become an abolitionist movement. They have one goal and are focused on it, but do not try to overreach that actual goal and infringe into other areas.