My guess would be the land! Try reading the 1950 book by Stewart Holbrook entitled 'Yankee Exodus' to see why people left New England during various periods. Before the Revolution, within New England people often migrated north-south. After the war when things settled down they looked further north (into Quebec) as well as west. Franklin Co., NY was one of those places however for some it was only a stopping place on the way to Michigan or Wisconsin. Some of the early (pre-1820) Franklin Co. land was being sold by Edward Ellice and the price was certainly attractive and not that far away for early Vermonters to settle. Some places within the county were not farmable therefore other products mainly potash and wood products quickly became the staples.