Parson Baker married a relative of mine in Missouri in the late 1870s. In an attempt to learn the name of the church, I decided to search for the minister in the 1880 census. After some searching, I found him, listed a a farmer. In many rural areas preachers or ministers may have had another "real" occupation and not even be listed as a "minister" in a census.
That preacher you are looking for may have marrid a lot of couples and given a lot of sermons, but the census taker may have written down "farmer," "carpenter," or something else as his occupation in the censs.