This rings incredibly true for me. I'm certainly the type of parent that lets my kids wander farther than normal (by today's ridiculous standard of normal anyway, which means within 5 feet) and I see constant looks of concern from all sorts of adults. My 4 year old is perfectly capable of being a half block ahead of me as we walk down the street and doesn't need an adult stopping him to check in. My last walk through the airport with two kids, both always well within eyesight, resulted in multiple concerned adults stopping in their tracks, ready to leap into action.

If a kid is clearly lost, crying, or distressed then please, by all means try to help. But if a kid is confidently walking without a parent within 5 feet don't jump to the conclusion that something's wrong.