It turns out, in fact, that it was a custom in Canada before the USA. Children in British Columbia around the start of the 20th century used to dress up in masks and disguises on 31st October and go house-to-house in their neighbourhoods collecting treats (fruit, sweets, biscuits) for their Hallowe'en night party. By the 1930s the tradition was well-established in the USA along with the spoken challenge "trick-or-treat". 
Even so, that's not the beginning of the story. Its arrival in Canada must have been as a result of emigration from Ireland and Scotland where the practice of 'guising' as it is called there dates way back to the 16th century, when children would dress in disguises on All Hallow' Eve and go collecting goodies (including special 'soul cakes' baked for the occasion) from neighbours in exchange for reciting verses of poetry or hymns - or leaving a curse if no treats were forthcoming.
And it didn't start there either. Imagine my delight when I came upon this snippet in Wikipedia:
I don't think there's very much tricking goes on these days, certainly not from parents with young children going the rounds of their local streets. I do remember stories from twenty or so years ago of teenagers going trick-or-treating and throwing flour bombs or eggs at houses where treats were not forthcoming. Nowadays I think the teenagers just dress up, buy food and alcopops and go straight to partying without the tedious business of knocking on doors for bounty.
I said I'd relate an episode from when my daughters were young. They'd dress up, we'd paint their faces and we'd go knocking on the doors of houses in ours and adjoining streets in Hemel Hempstead old town collecting treats, for the most part fun-size chocolate bars, little cakes, tiny boxes of candy or cartons of juice. We never recited poetry and certainly never tricked anybody. The girls, however, thought that they had been tricked at one house on the corner of a street, where upon knocking on the door they were presented with a Bible each rather than anything edible. It was quite a surprise, but they were suitably gracious in their disappointment. It was a reminder, I suppose, that All Hallows' Eve is at root a Christian festival as I stated at the outset.
I haven't written a political poem for quite a while (excepting about Gaza of course), but I've been getting a bit fed up with the antics of Fuhrage and the Nasty Party in recent weeks, and after listening to a political poem on the small boat furore at an open mic night this week, I've decided it's time.
Reform have been peddling their anti-immigration line, trying to suggest that immigration is at the root of all societal ills, pushing the boundaries of  'free speech' via their party canary Sarah Pochin, and canvassing quite hard to sign up members in the jewel of the north, so I thought I'd take the opportunity of today's blog to write something about disingenuous right-wingers, grifters, guising and political trick or treating. Here's the first attempt, not 'top drawer' poetry perhaps, but something I feel needs to be said, and it may evolve over time. 
Guising
Fear like a fog curls round street corners
and here they come looming in the swirl, 
feeling emboldened, quite without shame
spouting their thinly disguised racist bane.
Wise up. Foggy Frog Face is not your friend.
They'll knock doors, ring bells, insidiously
recruiting gullible souls. Don't let them in.
We know all is not well, but they'll tell us
the lie of the land, the illegals are to blame.
Wise up. Foggy Frog Face is playing a game.
Suddenly you're either a patriot or a traitor,
there's nothing nuanced in between, a trick
of snake oil conmen for generations to win
feeble minds to an egregious cause. Pause.
Wise up. Foggy Frog Face is untrustworthy.
A multi-millionaire and a narcissist, watch
as he toadies up to Putin and Trump, would
probably be Hitler's poodle if he were alive
today, out of lust for leadership and power.
Wise up. Foggy Frog Face is not good news.
In UKIP, then the Brexit Party, now Reform,
he's chanced his arm to win votes by plying
fear, sowing division and unrest, pretending
simplistic solutions treat complex problems. 
Wise up. Frog Face is no Prince in disguise.
Recognise the monster in his camel hair coat.
Even Enoch Powell refused to endorse him.
I think I'll get a sign made for my garden gate:
'No grifters, no conmen, no fascists, no hate'.
Wise up to foggy Frog Face before it's too late!
Thanks for reading, S ;-)