What irony can be found in the fact that the play, The Humans, takes place on Thanksgiving?

The action of the play takes place entirely on American Thanksgiving Day, one of the most important holidays in American culture and society. It commemorates the gratitude of the pilgrims (refugees / immigrants) for their safe and free arrival in a new land, in a new life. There are several deep layers of irony associated with this setting, the most obvious of which has to do with the fact that most of the characters in the play have arrived in a new life for which they are not grateful at all (but are struggling to be).