I agree that it is certainly drivable without a "anti-sway" bar but would definitely get it fixed if this is your daily driver.
All the talk about no abrupt maneuvers and no sharp turns is fine and dandy until you are in a situation where you can't help it, such as accident avoidance. You have no control of the cars around you, nor can you predict when an animal or pedestrian is going to lurch out in front of you.
There are all kinds of stories about guys that drive without anti-sway bars and have gotten away with it but that's no guarantee you will. It is there to control unwanted and unsafe body roll and if you drive on the street your rig should have one. Even a Currie Anti-Rock, which allows some slop, is better than nothing on the road.