I've heard that Halloween is second only to Christmas in the amount of decorations sold to consumers. It is not unusual to pass a house with tomb stones in the yard, a large spider on the front door, and a string of pumpkins circling the porch railing.
Halloween is a fun day for kids (and adults) who like to dress up. Costumes are sometimes planned weeks in advance. We look forward to the day when, for a few hours, we can become someone completely out of character: a princess, a witch, a super hero, etc.
Performing on stage, in a play or musical is another opportunity that has the same effect. We will always remember those special times when we left our routine lives behind, donned a costume, put on grease paint and acted out a part.
Shakespeare said, "All the world's a stage, and all men and women merely players. They have their exits and their entrances, and one man in his time plays many parts". He went on to enumerate seven stages of life between birth and senescence and death. His message was a grim one: that we really have no choice in the matter.
I believe that most of the time we live our lives, from day to day, and there's nothing very memorable about those days. But it is the times when we go outside of our everyday existence to dress up and act out a part, even a Halloween character, that are the days from which memories are made.