LOL, that reason alone should account for all females breastfeeding. Putting that aside for a moment though, there is nothing that ties Mother and Baby together more. You need to be physically together (which I don't see as a problem considering they are all on Voyager). The mother could easily arrange short breaks to feed her baby. Now here is the secret, once you get past the "need to be available" problem - No other way of feeding your baby is easier, it doesn't involve sterilization, it doesn't involve mixing anything, it's always at the right temperature. The only thing that would come close is the replicater and I don't think it has a chance against Guy's argument.