Below are job requirements from an actual classified ad from the NYT in 1966 for a stewardess:
A high school graduate, single (widows and divorcees with no children considered), 20 years of age (girls 19 1/2 may apply for future consideration). 5'2" but no more than 5'9", weight 105 to 135 in proportion to height and have at least 20/40 vision without glasses
In fact, a major recruiting point for the airlines was that a young attractive woman could find herself a husband working for their airline. She could then move on, have some babies, and make room for the next young pretty woman to have her chance. The whole "coffee, tea or me" way of putting it is rather vulgar but in reality, the airlines did not discourage at all the notion of stewardesses finding themselves a husband among the passengers. Having attractive stewardesses - all of which were available - no doubt helped the airlines sell tickets and so they would vie for the prettiest young ladies to join their crews.
It was a simpler time in America, where women were encouraged to "have adventures" early on but were then expected to find a husband, have some children and spend the rest of her days as a happy housewife and mother.
Which comes back to my post #4. Back in those days of high prices, a lot of the passengers were businessmen. Being a stewardess would allow an attractive woman an opportunity to meet successful professionals, chat with them in a relaxed setting, and perhaps arrange to meet them in a destination city where the businessman would be alone in an unfamiliar place, but where the stewardess would know places to go and things to do.
It was also a time where men and women from different education backgrounds teamed together to make a family.
Marrying in your education cohort was not necessary because back then it was admitted that one parent, mostly mom, would stay home with the children while dad provided.
So Lawyers married nurses, Doctors married nurses and teachers, and so forth.
That age requirement would tend to exclude college educated women, and indicate they were looking for attractive working-class women. The job would result in them meeting lots of men from higher income levels who might be suitable husband candidates and allow them to "marry up".