Well, Trick Or Treating originated with the Celts and then had a moment in medieval England. It was not until 1951, post WW2, that us Americans really embraced Trick or Treating.
I am rejecting the false claim that us Americans are to "blame" for Trick or Treating on Halloween.
www.history.com/news/halloween-trick-or-treating-origins
By the ninth century, Christianity had spread into Celtic lands, where it gradually blended with and supplanted older pagan rites. In 1000 A.D. the church designated November 2 as All Souls’ Day, a time for honoring the dead. Celebrations in England resembled Celtic commemorations of Samhain, complete with bonfires and masquerades.
Poor people would visit the houses of wealthier families and receive pastries called soul cakes in exchange for a promise to pray for the souls of the homeowners’ dead relatives. Known as "souling," the practice was later taken up by children, who would go from door to door asking for gifts such as food, money and ale.
In Scotland and Ireland, young people took part in a tradition called guising, dressing up in costume and accepting offerings from various households. Rather than pledging to pray for the dead, they would sing a song, recite a poem, tell a joke or perform another sort of “trick” before collecting their treat, which typically consisted of fruit, nuts or coins.