I am very sympathetic to nursing mothers, but this is a silly analogy.

If the major concern here is the infant, he or she is not eating off of a surface of the lav but off of mom's breast, a unit designed to function for the purpose in any number of environments, generally not sterile ones or even close to clean. Even today infants in the third world nurse in roadways full of blaring traffic, dust, and heaven knows what else. It's eat, or die. Seven billion former infants can't have managed to be that picky that a stranger's glance or noise or dirt in the surroundings would have put them off. If mom's breast is reasonably clean, that likely suffices - breast milk is full of antibodies in any case.

I don't think either had to move. Mom could have discreetly used a towel or blanket. She played the trump card not for her infant, but for herself.