Back in the 70's for Domestic flights, the additional cost of First Class was 20%, simple as that, and the red-eye flights (departing after 10pm I think) automatically reduce cost by 20% so flying First was the same as flying Coach on a Daytime flight.

I often paid the 20% with my own money, sitting in the upstairs bar in the old 747's was a great experience. Had a great experience in a Continental piano bar one new years eve - flying accross the date line, landing in HNL the year before I departed!!

Can't recall how one got into the clubs, but they were different. The Clipper Club at JFK back then had a special apeal for me, it was when flying was "special".

Then one day United and American started to hand out 50% discount coupons which started the FF programs, life's never been the same again....