As this is a blog about things to do in Greenwich I do not endorse leaving the area, but inviting more people into it is perfectly acceptable. The Westchester Airport is not in Greenwich (technically), but it is pretty darn close. With JetBlue and other major airlines flying into it, there is no closer airport or hub to pick up relatives (who wants to drive to Newark to pick up their mother in law?!).
For more information on the Westchester County Airport please visit its website at:
http://airport.westchestergov.com/