When you think about this, this answer becomes apparent. Settlers that arrived on a completely new continent didn't know many people there (if any). Moreover, it was possible that they left their family behind in the Old World, leaving them completely alone in the New world where they had to fend for them selves.
The only real community to be found was on the level of a village. People had to help each other, share in times of need, as they expected the others to do the same since the conditions and times they lived in were very harsh, but also laugh in times of happiness. All of this helped to develop a very strong sense of community in these villages.
