I found this via Facebook (a word of warning, it contains samples of lewd magazine covers and ads). It's about how society hypocritically condemns public breastfeeding when sexually provocative clothing and nude ads are considered normal and even win awards. Two women exposing themselves, one is OK, the other isn't. That's textbook hypocrisy.
The important differences here are first of all that sexually provocative ads degrade the body from the beautiful masterpiece of the Divine Artist to a piece of meat to be used for pleasure, whereas breastfeeding is not a degradation, but rather the fulfillment of the body's Divinely designed purpose. The other difference is that a woman breastfeeding in public will reveal <5% of her body (if anything at all) and is considered lewd, whereas the sexually provocative ads reveal 80+% of the female body and is considered "good" (because we don't want to be "uptight" or "prudes"). So showing your breasts in a sexually provocative manner, but not using them, isn't lewd, but if you use them for their natural purpose, even if you are not revealing them, then you're lewd? Is that the big difference? That you can show off your breasts all you want, so long as you don't use them for their correct purpose? But as soon as you start respecting your breasts and using them properly, it doesn't matter how much skin you show, you're lewd. So what then do we say to all this? What offends the world is obeying God and using things the way He designed them to be used. What pleases the world is pride and disobedience, perverting God's creation for what mankind considers "good". That's the difference. When you behave virtuously, the world is offended, but if you behave sinfully, then you are "good" and not "up-tight". That's why a harlot perverting her body on a magazine cover is OK, but a modest mother breastfeeding is lewd. The world loves vice and hates virtue.
When it comes to gaining proper respect for the human body, especially the female body, the most powerful intercessor is the Blessed Virgin Mary, not only for her obvious purity, but also because of the many images of Maddona Lactans, Our Lady of the Milk. Now I have no idea why there are parrots in the painting below, but the human body is a work of art created by God, not something to be used for pleasure, so therefore nudity has featured in sacred art for centuries. The Sistine Chapel ceiling (under which the popes are elected) and Michelangelo's David are the most famous examples. The Christ-Child appears nude in sacred art all the time, Maddona Lactans images in particular. Our Lady of the Milk is an important devotion for promoting proper respect for the human body, as it is about the body being used for it's correct purpose, not being degraded for pleasure. Also, breastfeeding is the particular issue pertaining to the body that we're talking about in the first place.