Halloween for Catholics is the smallest part of Hallowmas, which basically means that it is the eve of All Saints’ Day followed by All Souls’ Day.
In this way it is similar to Holy Saturday before Easter and Christmas eve before Christmas.
However, in context to All Saints’ Day, what are people trying to do?
On New Years’ eve, people traditionally blew up fireworks and made noise with the idea of driving darkness, winter and death away. As such, it is the final act of Christmas.
Halloween isn’t trying to drive death away, but embracing those who have died, perhaps “waking them up” so that they may attend the saints the next day.
Even cultures far removed from Christianity have similar events, days to honor the respected dead. To show them that love remains.