This year it was irrelevant because it was basically cancelled
However in normal years its not right to put your beliefs on some little kid who only wants candy. If dont want to answer the door and keep the lights off (Like you are not home) that is fine , but its very different to open the door and tell some little girl dressed as cinderella, I dont celebrate Halloween and I have no candy for you. Its a tremondous Chilul Hashem to do that.
Again dont want to be bothered, Shut off all lights and pretend you are not home and if they ring the door bell dont answer