Interesting, Izzy. I think you're right. I suspect it's a little like smoking - they're either going to go do the same thing or be repulsed by it.
I put a high priority on safety, but I also believe that we should teach our kids to be independent, and give them the freedom to explore it as they're ready for it. There are lots of little steps along that path, and sometimes we stall for one reason or another, but if we never lengthen their "leash" how will our kids ever learn to be self-sufficient and be able to handle it when we expect that of them?