all earnings were butt-in-seat miles (with the 500-mile minimum, same as today; I don't recall whether class-of-service bonuses were a thing), and there was no dollar component or credit card affiliation incentive in any airline program

for the first few years of Delta's program they had a 1000-mile minimum credit per segment (!!), and most rental car partners credited at 500 miles per rental

one of the best rewards in the mid to late 80s was TWA's 50000-mile redemption for one free domestic F ticket and one upgrade to F for another passenger on the same reservation; I believe it also included coupons for a free one-night hotel stay at a partner property AND a free two-day Avis rental