Why are apples seen as the “default” fruit in Western culture? The answer involves Greek myths, Latin spelling mistakes, and English semantic narrowing.
Why do we blow out candles on birthday cakes? The answer involves Egyptian theocracy, the moon goddess, and (as for many holidays) the mixing of Christian and pagan tradition.
Why do we cut down evergreen trees and decorate them with glittering ornaments and lights during the Christmas season? The answer involves the sun god, the Garden of Eden, and Charlie Brown.