Fear seems to me to be the answer much of the time. So much of the Church seems so afraid of this or that sin, or this or that group, they seem to believe if they can just beat it into some form of submission, of cleanse their part of the Church from any visible hint of it, then God will bless them, their church or their nation etc . Like the Pharisees who were obsessed with enforcing a certain kind of holiness in Israel believing it would bring in God's Kingdom to world, so a similar spirit can happen here.
It is nearly (and sometimes not so nearly) idolatrous in a way, people can become so focused on sin, and working out all the minutiae about it, and so focused on destroying any hint of it, they make the fear it their god and idol and don't look to Jesus, they don't worship and rejoice in Him. Like the Older brother in the Prodigal Son parable, they stand outside the feast by their own choice, and in all this they don't live in the freedom and liberty that God wishes them to live, living a life of faith working through love, and of righteousness out of love for Jesus and By His Spirit, but instead remained bound and trapped by pride, fear and hate.
Perfect love casts out fear, and many of these need our compassion and prayers to return to the feast God has for them, and wants them to enjoy.