There's no way they'd have Betty breastfeeding! The show is full of period-specific parenting, from letting the kids tumble around the backseat with no seatbelts, leaving their picnic litter all over, pregnant ladies with a cocktail in one hand and a cancer stick in the other, kids mixing cocktails for the parents, to Betty's little girl putting a drycleaning bag over her head, and Betty getting mad because she dumped out the clothes it contained. They've bent over backward to shock contemporary parents with all the horrible stuff THEIR parents did, and formula-feeding fits right in.
How would she even get a breast out, with all those Merry Widows and full-body girdles and gorgeous shirtwaist dresses that I would give my eyeteeth to possess?

It must have taken women 45 minutes to get their clothes off every night -- I don't see how all those lunchtime affairs ever worked out logistically.