Hello - You have touched on this interesting aspecct of genealogy and migration which is known as "Cluster Genealogy" . It simply means that family or community groups often migrated together. For example in Centre Co PA my Wohlford extended family included the Kleckners and Snooks. When the Wohlfords picked up and moved to Stephenson Co. IL so did the Snooks and Kleckners too. I will bet you can find some of their former neighbors near by too. The Snooks eventually settled in the next county south.
Similarly, although not a migration west, I am trying to find where my Averys came from before living in Bradford Co PA. By applying Cluster Genealogy, I am looking for where their neighbors and some families they intermarried with were from This strongly suggests that they may have been from Scholarie (sp?) Co NY as there were Blodgetts and Vromans from there. This may assist people with breaking through their brickwalls.
Google Shoes Strings Genealogy for more information.