Not mockery at all. It was just seeing the mentions of Rose West and Myra Hindley made me realise that women aren't less threatening at all. Having been told in no uncertain terms that, no, it would not be OK for me to speak to a child/teenager in the circumstances I described, I'm afraid that my wandering mind thought about all the times I walk with my daughter and whether that would be more or less frightening. Then, I thought, well, if we were dangerous if we spoke, we'd be dangerous if we didn't speak, logically.
I didn't intend to sound mocking with the (in hindsight) ill-advised psychopath remark. It was just that I was gradually being made aware of how a seemingly innocuous question could be regarded as frightening if the person speaking was unknown to the child/teen and then I went on to think that someone with ill-intent doesn't need to speak to be viewed as a threat. It made me feel as though just being there would be the wrong thing to do, hence the "I think I'll stay in" which could be construed as petulant, but wasn't meant that way.
I apologise if I've annoyed with my questioning. As a mother I'm only too aware of how parents fear for the safety of our children. Even when they're adults we don't stop worrying because reaching adulthood doesn't make you impervious to harm.
I know this is a very long post, but I hope that it has been read by some, because I really don't mean to annoy and have tried to explain my thought processes.