The way I saw it: the bible says if you have something against your "brother" you should approach them.
Yes Matthew 18 as I recall, I dredged that up from somewhere! Nobody paid any attention to that scripture did they LHG? Yes I remember a lot of shunning without any platform announcements, marking I think they called it. Anyone could mark a person they decided was unsuitable association I think.
Very small-minded I agree. Fortunately they are not doing anything significant because it's a wonder anything gets done with so many people refusing to speak to other people. Hilarious isn't it. A control mechanism yes. You just have to refuse to be controlled.