I grew up in a predominately Mennonite Brethen community. The majority of the population was MB and it was the biggest church in town. However, we also had a Catholic, Anglican, and United church.
The MB church forbid celebrating Halloween. The pastor was my neighbor. All of his flock had their lights out, no candy, and they all flooded to the church for 'games and crafts'.
My friends and I were rowdies. We caused mischief, got as much candy as we could, pulled good natured pranks, and dressed however we wanted! Halloween was always a chance for us to indulge ourself: We could transform into a nasty creature for one night, or a playful creature, and it was a safe expression of parts that normally need to be socially toned-down.
As an adult, I still enjoy going to costume parties and being as wild and crazy as all hell. It is one day of the year to celebrate like a good pagan