Tell that to God. He needs to lighten up. Obviously, we should observe the world and do the things in the world...just join up with them...no need to set ourselves "apart" from unbelievers....just follow their customs.
1 Peter:2:9
But ye are a chosen generation, a royal priesthood, an holy nation, a peculiar people; that ye should shew forth the praises of him who hath called you out of darkness into his marvellous light;
2 Corinthians 6:17:
Wherefore come out from among them, and be ye separate, saith the Lord, and touch not the unclean thing; and I will receive you.
2 Corinthians 6:14:
Be ye not unequally yoked together with unbelievers: for what fellowship hath righteousness with unrighteousness? and what communion hath light with darkness?
This Halloween worldy day is pure satanic....it celebrates death, darkness, and demons. God's people should have nothing to do with this day.