If you had been a mother in the 1950s do you think you would have breastfed your babies? In all honesty, I cannot say with certainty that I would have given the incessant advertising then that linked bottle-feeding to wealth. We are lucky to be living in a time when medical professionals and researchers all agree that the breast is best. Actually, doctors knew that then too, but advertisers were exceptionally aggressive with bottle-feeding messages.
Surprisingly this ad is not for a formula company. It's actually an ad for the Electric Institute of Washington, hence the mom putting a caboodle of baby bottles in the refrigerator. The only way an electric company could have gotten away with advertising a baby drinking from a bottle is if it was a common practice among their target market. Apparently in the 1950s it was.