As Christians we are continually (and correctly) reminded that we must adhere to Bible principles, because then we can appreciate the teachings and reasoning behind many scriptures. Applying the WTBTS doctrines presented to us as Bible-based fact, we must "strain out the gnat and gulp down the camel" (Matt. 23:23,24) by ceasing forthwith from the preaching work.
The justification is simple; by applying the Society's orders as to how we must treat disfellowshipped ones, we must take heed of Christ's words at Matthew 18:17 "If he does not listen to them, speak to the congregation. If he does not listen even to the congregation, let him be to you just as a man of the nations and as a tax collector", and treat worldly people in the exact same way - we must shun them totally!!!
Further proof of principled action (if required) is found in the misapplication by the Org of 2 John 10 "If anyone comes to YOU and does not bring this teaching, never receive him into YOUR homes or say a greeting to him."
Therefore, by definition, we must shun people of the world, because they try to give us their personal thinking on what the Bible teaches - something which warrants the figurative stoning to death of a brother or sister!
On the other hand, Jesus spoke of the "weightier matters of the Law, namely, justice and mercy and faithfulness.