I wish every neighbourhood was like yours MrsCakesPremonition.
I don't take part in trick or treating, don't have any halloween decorations up, don't have a carved out pumpkin, yet still other parents, who I only really know to say hello to at the school gate send their DC to knock on my door. I'm talking more about the little ones, which is why I mention their parents.
When I don't answer, they persist in knocking for quite some time, sometimes they shout through the letterbox, before going on their way.
I have always made sure all the lights are switched off, so there is little sign of life in my house on Halloween night, but my car is sitting in the drive, and they still knock.
I have now resorted to going out for the evening, no car on the drive, no lights on, and best of all, I have no idea whether the local children are knocking or not.
Just because you know someone in passing, it doesn't mean they want to take part in trick or treating, even if they have DC of their own, even if your DC know their DC, so unless it has been arranged between parents before Halloween, or you have Halloween decorations/a pumpkin in clear view, don't assume people are taking part. I'm sure most people appreciate this, but there are too many that don't.
I hear of many people, some elderly, who turn all the lights off and basically hide in their homes on Halloween night. 