Since this thing always gets so much buzz, why isn't it part of the menu all year? McDonald's told Huffington Post that it doesn't really sell all that well, it just has enough of a fan base that they bring it back each year as a kind of customer outreach. Translation: it is purchased by the same hipster doofus types who now think it is cool to walk around with Walkman's and cassette tapes.
Maybe retro hipsters need to discover the McDLT. Here is Seinfeld's "George Costanza" dancing his way through 1985 about it.