It is amusing that someone could possibly relate the feeding of an infant to defecating, urinating, or having intercourse in public. It violates no code of health, safety, or decency. It is not obtrusive. It is not perverse nor explicit. More often then not there is very little, if any, bosom showing - and regardless of how the mother is dressed the only area of the body which is currently deemed unfit for viewing in America is quite certainly covered by a child's mouth during the act of nursing. Breastfeeding is a healthy part of being a loving and skilled parent. That's not something I feel needs to be kept to myself.
Anyone who is uncomfortable with witnessing someone nurturing their child is free to look away at any time. I wont follow you, promise.