Importance of Babies' First Year Feeding Process

This subject has been on mind for a long time and I feel compelled to write about it. I have observed when some mothers feed their small babies they either hold the baby in front of the them on their knees and away from their chest, they do support the head with their hand; or they feed the baby lying in a crib or in a pram or on the floor. I observed this feeding process much too often in the past, I have even seen it in some movies, which keeps me always wondering why some mothers feed their babies in this fashion and where did they acquired this method?