Being a parent has some really gray areas at times. Such as strangers...
I grew up in a small town. So much so that I invited my 6th grade teacher to my wedding (yes, I kept in touch with her, and her husband who was my high school counselor, after a mere year in school). Living in a small town like that granted you a lot of freedoms. When I was 12 or so, I would ride my bike about 2.5 miles by myself, or with a friend, to the local baseball card shop to get some new packs or trade some singles. The donut store was right next door, so we'd get a donut and play a few video games. I met a lot of new people this way, mainly older folks, and had a few interesting conversations. If you said "Hi" to somebody in the parking lot, sometimes you could wind up chatting with them for a while. It was just the way things were. Sure there were strangers that you had to stay away from, but often enough they were the ones that matched the stereotype of having shifty eyes, talked to you weird, and generally gave off a bad vibe.
Nowadays, things are drastically different. I live in a different small town, and overall people are quite friendly. However, we make sure our twin girls (both 5) stay away from everybody, except for the proper authorities, like teachers at their school, policemen, and firemen, etc. We live next to a trailhead, so there are a wide variety of people that will walk by any given morning, some with dogs, some without. They all look quite friendly, and we've talked to a few and allow the girls to say hi to them. But by in large, we have to tell our girls to stay away from the fence when people walk by. We just don't know who is going to take them away.
It's sad. They really want to meet new people. I really want them to meet new people. There's a wealth of wisdom and experience out there that I simply don't have, and meeting new people and hearing their stories is wonderful. But what do you do?! I try to get down there when new people are coming by to say hello and help introduce myself and the girls, but I can't always make it down there. So I tell them to stay away. Don't talk to strangers. Stay away because our world has become loaded with lots of dangerous people who want to harm you. Stay away from potentially amazing stores about places you or daddy have never been to before. Maybe they're just too young still. Maybe people are just that more untrustworthy.
[:: sigh ::] What do you do?