While trusting someone with your physical safety should be a 
     high-trust decision, we treat it cavalierly enough in our day 
     to day lives that most people clearly don't worry about it.

We just can't avoid it. We assume that nobody's poisoned our food, we assume that nobody is going to go suicidal on the roadways and ram themselves head-on into our car, we don't wear body armor to work because we assume our coworkers won't shoot us. We even assume that the anestheseologist at the hospital isn't housing a wicked hangover that will prevent him from doing his job.

Essentially our lives are in other peoples' hands pretty much 24/7!