Hey guys, I have a 2011 Ford Ege Sport and have the same problem. I have called just about every distributor and nobody has a hitch that will fit the sport model yet. Also, nobody has a definitive answer as to why the one for the limited model wont fit and why they don't offer one from the factory. I did however contact a major distributor and spoke with the enginerring department and we may work something out where I drive my vehicle to their facility and they will fit a hitch to my truck and make it standard for all 2011 sport models. I will update this post as I get new information.
BTW, I traded in a 2007 Nissan 350Z Roadster for my 2011 Ford Edge Sport and don't regret it one bit. I love the edge and with AWD and the added HP of the sport it handles and performs awesome!