Breastfeeding itself is not a sexual act, but neither is urinating.
But since urinating exposes the penis, doing it in public is still indecent exposure.
By the same token, since breastfeeding exposes the breasts, doing it in public is indecent exposure.

What Girls & Guys Said
1 0Nah by that logic Men taking off their shirts is indecent exposure. We can see the nipple. When breastfeeding you don't even see it anyways
male nipples aren't a private part, female breasts are.