I wouldn't walk around with my breastfeeding shots plastered on my back for everyone to see as I go through my day, and I'm not sure why others would publically share these types of photos? I guess I'm just private that way.
Similar to the laws here in Ontario, Canada where woman may legally go topless (though this rarely seems to happen) so long as it isn't done in a provocative manner. While our breasts have been sexualized by the media, they are perfectly natural and breastfeeding is the purpose of their existence. Maybe Facebook can adopt the same strategy - this could make it so that even breasts that are covered but are displayed in an overly provocative way (i.e. wet t-shirt for example) wouldn't be allowed while breastfeeding shots.
Again, I'm surprised the conversation is even necessary.