Well, I also don't personally want to run my life the way juliehry does, but I personally wouldn't call her an "extremist." I disagree with her views, but I respect her desire to, in her mind, put her kids' safety over her own selfish enjoyment.
My wife is a pediatrician, and I am a therapist who works with children and adults AFTER they've been in horrible, life-altering accidents. She and I have seen it all. We know that bad things don't just happen to "other people," because we've both (separately) treated those unlucky "other people." Even with all this knowledge, we're still fine with taking our kids on Disney Transport buses, and NYC subways, etc. It's all about personal decisions, about what you think is reasonable, and what you can live with and what you can't.
Some may call juliehry an "extremist," but on the other hand, she'll probably never know me. That's a good thing. If I come to your home to provide treatment, it's because a horrible, horrible thing happened to a loved one, and that loved one will never be the same again. Of all the people I've treated who were injured as a result of a motor vehicle accident or bicycle accident, I've NEVER treated a patient who: was wearing a seat belt; who was in a child safety seat; or who was wearing a bike helmet. Never ONE.