Nicholas Rogers, a historian at York University says that when people prayed for the dead at Hallow Mass, they dressed up. When praying for fertile marriages, the boy choristers in the churches dressed up as virgins. So there was a certain degree of cross dressing in the actual ceremony of All Hallows Eve
The best part of any holiday (besides the food) is dressing up. Whether its Fourth of July or New Years Eve, putting together the right outfit is key to starting the celebration, and no other holiday calls for outrageous and funny costumes like Halloween.
After a brief lull during the sugar rations in World War Two, Halloween became a widespread holiday that revolved around children, with newly built suburbs providing a safe place for children to roam free.