I've read on these boards that you can order it (and the pretzel bread) as take out from the Le Cellier check-in podium. Based on the posts that's all you can order as take out and they will only do it when they aren't busy (when is that?!?).
During the F and W festival since they have to make such big quantities they make a different recipe that uses a commercial soup base rather than homemade as they do during the rest of the year. This is the soup at Le C and the booth during this time frame. I'm not sure if this affects the taste at all but I'm allergic to soy which is in commercial soup base and they are always very honest about how they make it.