My wife and I have two girls and she is still a size 2.
To be honest, many of her friends who are also mothers are jealous of her since she was able to keep most of her figure (though her size hasn't changed, motherhood has changed her shapely figure

).
Her chest has also not changed in size though she breast fed both girls until they we're each roughly 2 years old. After that, they had already learned to drink milk glasses with also a bottle each day of powdered milk (they seem to prefer it over the real thing).
My wife, while still breast feeding, on occasion had to feed either girls in public while we we're out since they got very hungry. Being a perfectly natural situation, it never occured to me to object.
While it's true that many mother (especially in North America) are obese and the sight of them breast feeding is rather stomach-churning, we can't dispute the the action they must take in feeding their child while left with no other option. We can only dispute the fact that they are fat, lazy and disgusting for letting themselves deteriorate like that.
Luckily for me, my wife respects herself more than your average trailer trash.