Answer:
The Amish interact with modern society and popular culture during their annual mud sales, in Lancaster County, PA, where the majority of them live (at least in Pennsylvania).
In these sales, the Amish offer the public many products, from clothing, to animals, to agricultural products like dairy and other groceries. In this event, the Amish obviously have to interact with modern society and popular culture, but they still keep their own traditions and old ways.