I can't think of any one thing in particular but I do remember some congregations being more lenient in some things than other congregations. But never in anything that was considered a DFing offense. It was usually "gray areas" or conscience matters. Which, when you think about it, is silly. If it's a conscience matter, then shouldn't each individual make that decision based on their own conscience?
I have seen bodies of elders(in a single congregation) break off into seperate factions because they don't agree on something. It usually was due to one elder and cronies being very conservative while another elder and his cronies were more liberal minded. I remember one elder had a thing about long hair. I don't mean pony-tail long, but touching your ears/collar long. Other elders thought it was being rigtheous over much and nit-picky, but this one elder and his entourage of ass-kissers went around giving all the young brothers hell about their hair and grooming. The young brothers would run to the other elders who told em to not worry about it. Well, that lead to disagreements on the elder body, which brought out even more resentments lying under the surface, which in turn spread throughout the congregation, causing major problems as time went on. All because people just can't mind their own damn business(1Thess. 4:11)