purple for Halloween?

When did purple become a designated Halloween color? Suddenly, this year, it seems to be everywhere: in the halloween-themed dog toys we bought (yes, we celebrate any and all holidays by buying dog toys and having a little party out in the backyard), in the halloween lights (?!) and garlands (!?!) various neighbors have strung up, and in other decorations I've seen in stores and on houses. I guess the traditional orange-and -black combo was too garish, or orange lights look too much like construction trucks. (um, and when did we start stringing garlands for halloween, either?) Or it's just the wide spread prejudice against orange. People really don't appreciate the color. Purple, of course, has a long history of associations with royalty, with witches, and with gay folk. And I'm a big fan of purple, don't get me wrong. I just don't associate it with Halloween.