Nancy Schwab loves Christmas. Really, really loves Christmas. “I have Santa collections from when I was little,” said Ms. Schwab, 62, a retired school administrator. Thus, it became a source of annual annoyance that decking the house with boughs of holly (and twinkly lights) was frowned upon in her Joliet, Ill., neighborhood until Thanksgiving had come and gone. Almost two years ago, Ms. Schwab and her husband, Robert, a retired carpenter and contractor, began to contemplate relocating to a place with a vastly different feel. “We started researching, and Santa Claus, Ind., came up,” Ms. Schwab said of the town in the southern part of the Hoosier state that bills…