My ancestors fought for my freedom also, and yours. I expect most of them would agree that if your company does not want you to have dreads you should not have dreads. You work in a service industry where image is important, your company knows this and wants their crew to look smart and professional, you may look very good with dreads but they have to draw a line somewhere, so if no dreads is the policy then I am afraid its no dreads. Good luck if you decide to be stubborn and use the racist card even though it is the same for crew of any race. All you are doing by this is devaluing what your ancestors fought for which I am sure was not so that their descendants could get past rules for everyone by claiming it is racist.