Every Chabad tallis katan I have seen does not have fringes along the bottom, but it seems popular to have them on other types of tallis katans, particularly other Chassidishe ones.
Here's a normal Ashkenazi tallis katan. See the fringes along the bottom? (Photo courtesy of Ben's Tallit Shop)
Or here's a rather large picture of a Chassidishe man wearing a tallis katan, where you can obviously see the fringes. (Photo courtesy of Wikipedia)
But when you see Chabad tallis katans, I've never seen one with fringes like this! I notice that most (if not all) Chabadniks wear their tallis katan under the shirt, and so there is no need for the decorative fringes, I guess.
But has anyone ever seen one with fringes along the bottom?