I stumbled today upon the name of my father’s 4H group he was a member of in the 1950s–the Elvaston Strait-Shooters. There were 4H clubs nearer to where they lived and the reason he and his brother were members of this group instead of one of the nearby ones has been lost to history.
There are a variety of organizations–including church–where your ancestor may not have attended the nearest one. There are many reasons your ancestor may have not attended the nearest church of her denomination. Your ancestor may have been a Mason, but may have been active in a group that was not nearest to where he lived. Sometimes people have a falling out with the nearby group (or church) and change their membership. Sometimes people move away, but choose to remain a member of the group they were initially a member of.
But don’t assume that your ancestor was a member of the nearest “local unit” of his club or organization. He may not have been.