My main concerns are:
1. The 'strangers' thing.
2. The idiots that think it'll be clever/funny to give the children something dangerous or that will cause stomach upset etc.
3. People who just don't want to get involved for whatever reason and are disturbed by callers.
4. Older people who may be in bed, may be scared of callers after dark.
I'm not keen on the whole 'knocking on doors - asking for treats' thing but my wife takes the young'un out with some of his pals and their mothers. They have a rule, if the house is decorated for Halloween then the kids are allowed to knock/call on the house, if the house isn't decorated, they're not allowed to call on it. Thus avoiding scaring/worrying/disturbing older householders, those without children that don't wish to get involved, etc etc. We have some decs up (for his benefit), and i'll no doubt be given a big bowl of sweets to hand out to callers whilst those two are out. As I say, I'm not keen on the idea but most of the kids know us/me (through the time I spend at the school), so I suppose I'm not really a 'stranger' but all the same, I understand the argument of 'Don't speak to/accept sweets from a stranger' and yet that all goes out the window one day a year. However, I don't want my hangups to get in the way of him enjoying his childhood so I bite my tongue and do as I'm told... once a year isn't too much to ask I suppose!
When we were kids, me and my pals used to go out doing 'Penny for the Guy' around Guy Fawkes so it'd be rather difficult for me to argue the 'begging' thing.
Regarding point 2 above, if the likes of think it's clever to give children something noxious as a joke/because they don't want to be called on, etc, Even though I'd be terrified of such hard cases,
I'm MORE than willing to have a little chat with them.