Later the same night

After the guisers had gone home. The streets were thick with them when I arrived an hour earlier.
(I'm inclined to agree that modern-day Hallowe'en is the 'Japanese knotweed of festivals' as someone put it.)

I'm in London for a 93rd birthday.  Fortunately no-one knocked at the Old Man's door.
He once asked me, puzzled: What is trickle-treating?

No, he actually said  "Why do children keep keep knocking on the door and saying Chickadee?"
It was my elder son who called it trickle-treating - when he was very little.