If my memory is correct, the Saturday night stay required for some discounted fares began in the years immediately before deregulation became effective in the U.S. If not, it became the norm on the lowest fares offered from the earliest days of deregulation.
Speaking of the unconscionable disparity that has developed between fares typically paid by business travellers and leisure pax on all of today's major airlines (except WN), the difference was far less back when "super-saver" discount fares were introduced in the mid-'70s. Until well into the '80s, typical savings over unrestricted coach fares were 20-40%, depending on amount of advance purchase and other restrictions.
Compare that with today's fleecing of business travellers who often pay 4-10 times the fares paid by others on the same flight, in the same coach cabin, all of whom are experiencing the same service which is mediocre at best. Herb Kelleher said it well when he once referred to the pricing practices of the U.S. major airlines that are obviously tailored to gouge business travellers and others who are unable to book ahead as "outrageous, opportunistic."
Southwest practices what Herb preaches; in most instances the difference between their unrestricted and lowest discount fares in the same market is less than double. Only when WN is offering "$99 each way based on round-trip purchase, airport and flight taxes additional" on their longer routes have I seen their unrestricted fare price at (slightly) more than twice the amount of the lowest fare in the same market.
IMO, the U.S. major airlines (with the exception of WN) have painted themselves into a predicament with their pricing habits over the past decade. While smugly supposing they could go on and on fleecing enough business travellers to offset the give away fares offered, as needed to ensure that their planes flew packed to the point where airline service became something of an oxymoron, two things happened, the brunt of which is reflected in recently released second-quarter results.
Even while load factors remain high, most U.S. majors are awash in red ink for two reasons:
1) The line was crossed in the price the business travel market is willing to bear. The economic downturn made the businesses paying the travel bills rethink their runaway cost of air travel. While a considerable amount of business travel continues to take place, travel managers have "discovered" that, in many instances, trips can be planned far enough in advance to take advantage of discounted fares. Far fewer are willing to pay the confiscatory fares that airlines supposed they could depend on exacting from business travellers.
2) As fares paid by business travellers soared out of sight, the same airlines took on an increasing propensity to price non-business travel in a manner to ensure their planes were packed at any price -- as in conducting fire sales wherever and whenever needed to satisfy their obsession with oversold, overcrowded flights. As a result, not only has airline service declined sharply; leisure travellers have become more astute in beating the airlines at their own fare games: hold out on the airlines until they panic over the number of unsold seats in their inventories and initiate the next round of fire sales.
Airline yields are taking a significant hit on two fronts, it appears. IMO the losses that most of the U.S. majors have experienced in the first two quarters of 2001, even while load factors remain high, is a case of "what goes around comes around." The U.S. majors who are losing their millions painted themselves into their current dilemma with their wanton disregard for equity in pricing -- IMO, as more and more travellers have learned how to beat the airlines at their own games, the U.S. majors are reaping what they have been sowing for most of the past decade.