"Pretty sure the Amish don't celebrate with Christmas trees."
Yes, no, maybe, it depends. There's no easy answer, because Amish is a catch-all term for people who have the same set of core beliefs but differ pretty substantially in how they observe them. In other words, not unlike Jewish, Baptist, or Mennonite.
It all depends on how strict that particular sect is and often what part of the country they live in as to how they observe Christmas. My family has gotten Christmas cards from the Amish in years past. My Father and Grandfather had a lot of contact with the Amish in Mifflin and Juniata counties in Pennsylvania over the years because of their engineering professions, and that led to holiday exchanges and the like.
It's generally true, however, that the Amish don't go all out on commercialized celebrations like most of us do. Their celebrations generally tend to be more family and community oriented, but they do tend to go big on the food, just like most of the rest of us.
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