We often serve traditional foods at these meals. Internationals like the chance to be in an American home and experience the traditional foods. Depending on which country they are from, some foods like mashed potatoes or pumpkin pie are not a favorite.
There are a number of reasons for doing this on Thanksgiving and Christmas.
We like seeing people enjoy themselves who would not otherwise have much social life on Thanksgiving and Christmas. We've heard from a lot of people who don't have faithful Christian relatives and friends that these days are hard for them. In most Plain Anabaptist churches, nearly everyone else in the church is either heading out of town or being with relatives nearby.
I got to experience this first hand years ago whenever I was part of a church with four patriarchs and their descendants. The four family trees did things with each other. Occasionally they would invite a single like me to their family get-togethers which was nice. Once I was married this didn't happen as much. So the rest of us who didn't have relatives in the area would do things with each other.
We have observed over the years that churches who want to grow their churches to be something more than ethnic Anabaptists, are intentional about making non-relatives apart of their social circle.
And when we doubt whether this is the right thing to do on Thanksgiving and Christmas, we remember these words of Jesus, and the doubts go away.
He also said to the one who had invited Him, “When you give a lunch or a dinner, don’t invite your friends, your brothers, your relatives, or your rich neighbors, because they might invite you back, and you would be repaid. On the contrary, when you host a banquet, invite those who are poor, maimed, lame, or blind. And you will be blessed, because they cannot repay you; for you will be repaid at the resurrection of the righteous.
“One was founded on profit. The other on faith. 
