In my experience with traveling outside of the US - this is a pretty American thing. Most countries that aren't being led by Drug Lords (i.e. with strict gun controls, adequate medical care, and an understanding of the severity of mental health) don't live in constant fear of kidnap/rape/murder.
When I was three I got lost on the beach. I vividly remember being afraid that I couldn't find my parents, but also afraid of talking to a stranger, even though I knew I needed an adult.
Thank god this was in the 80's before your average adult was afraid to help out a child who was in obvious distress. If that had been today, who know what would have happened.