Many homeowners during Christmas put (electric) white candles in each window instead of Santas, trees, or tiny reindeer. Is this just an outbreak of subtle good taste or is it of religious significance, i.e. they’re Jewish or Mormon or nothing at all but still want to be festive in December?
This custom has its origins in the idea of lighting the way for the Holy Family as they journey to Bethlehem. It’s pretty – I do it, with electic (not real) candles to avoid the fire hazard.
It’s just another way to decorate for Christmas. Some people put up Santas; others put lights in their window. The useage of lights for decoration probably has something to do with the fact that Christmas falls when there’s the least amount of daylight.
I suspect that some people got tired of the garish Santa and multicolored moving lights, so they went to something more simple and understated.