It seemed to me that the only way someplace could stay in business if they were giving discounted tickets to buyers and a commission to the company, would be to raise their prices for the people who weren't buying through the discount service.
My grandmother knew she was having twins in 1933. I don't know how it was determined. It really didn't change the birth plan (my grandfather left my grandmother with relatives and took his trip to Europe anyway).
My father used to talk about trying on new shoes at the store then putting your feet into an x-ray box to see if you still had room to wiggle your toes. Fear of radiation didn't start until we bombed Hiroshima and Nagasaki.