L.A.
This is normal.. Children like being scared, but sometimes, it gets the best of them..
Is he afraid of going Trick or Treating? Ask him.
If he does not want to go Trick or Treating, do not make him.
Let him know you just want him to pick out something in case he changes his mind.
He can hand out candy..
Or if he has somthing already at home.. have it ready for in case he changes his mind.