I was gonna rant on this but jinx took care of pretty much all the arguments.
I think this impulse to hide the real function of breasts is probably some remnant of the a middle-class 50's hide your woman in the house, better living through chemistry, culture. Thats over now, move on. Breast milk is more available, cheaper, easier to digest, and designed by (evolution) (God) whatever to provide everything your baby needs (and it takes the baby weight off!). Of course these are just the thoughts of someone who was raised in a conservative Catholic household and was breastfed in church every Sunday as a baby.
I'm still waiting for someone to photo shop W into that picture.