This has always been the frequent flyer’s equivalent of the chicken-or-the-egg riddle: Do the big airlines give $198 leisure travelers $998 worth of service or do $998 full-fare business travelers receive $198 worth of service?

During the first days of deregulation, in the early 1980s, the airlines could straight-facedly claim that $198 leisure travelers received all the perks and benefits accorded to the $998 business traveler.

In recent years, of course, that claim wouldn’t pass the laugh test and not even today’s clue-less crop of airline executive would dare make the suggestion. It is now taken as gospel that everyone gets $198 worth of service and what you pay–$98, $198, $498, $698, $998 or $1,298–is between you, your gods, your fare-scrapping software, your travel agent and the yield-management computers.

But now, I believe, we may be entering a dangerous new phase of big-airline service philosophy. I suggest to you that today business travelers are getting $198 worth of service and leisure travelers are beginning to get $98 worth of service for their $198 fare.

I refer, of course, to a phalanx of seemingly unrelated moves that the airlines have made in recent months to reduce the service provided to our seatmates, the $198 leisure travelers. Despite all the fare sales you see advertised, the lowest leisure fares are now available only if you book directly with an airline’s proprietary Web site. Delta and Continental’s frequent-flyer programs no longer offer full elite credit for low-fare tickets. Some low fares don’t accrue frequent-flyer miles of any type. After several rules fiddles, airlines slap huge change fees–$100 domestic and $200 international–on the cheapest seats, which are already nonrefundable and were briefly in the use-it-or-lose-it category. All carriers are tightening their upgrade rules: the lower your fare, the less likely that your ticket qualifies for an upgrade.

And this week, another of the big airlines’ seemingly endless collection of annoying other shoes began to drop: Air Canada let it be known that its lowest-priced tickets will no longer include advance seat assignments. “Some fares will have the ability to choose your seat for free and some fare types may require a charge for seat selection if you want one,” an Air Canada vice president told the Montreal Gazette.

To make matters worse, the major airlines have been quietly suggesting that these leisure-fare restrictions are an enhancement of our perks. The limited distribution of cheap seats is only fair given how much more business flyers pay, they say. Delta and Continental insist that slashing elite mileage for low-fare flyers means more upgrades for high-fare flyers. And the Air Canada apologist, Montie Brewer, vice president for commercial operations, says full-fare travelers will now “see the value that they’re purchasing relative to other price points.”

Worst of all, some business travelers, desperate for any sign of preferential treatment from the carriers that overcharge and abuse them, are actually buying into the airlines’ less-for-them-is-more-for-you spin.

“It’s about time the airlines crack down on the backpackers,” said Richard Torlonson, a frequent-flying salesman from Pittsburgh. “I should get some benefits for the price I pay,” he told me recently.

“Bravo!” wrote Susan Riordan in an E-mail she sent me from a hotel room in Chicago. “Finally, the airlines recognize we pay the freight,” wrote the Los Angeles-based marketing manager.

Much as I agree with the sentiment, I feel compelled to ask a brutally obvious question: How does taking away another passenger’s privileges translate into the airlines recognizing our superior financial worth as frequent flyers?

When the airlines take away a leisure traveler’s benefits that doesn’t mean a business traveler is getting more. Look carefully, fellow full-fare flyers: You don’t get lower fares because the airlines now offer their cheapest seats only on their own Web sites. You didn’t save anything when the airlines upped the ticket-rewrite fee. No matter the tortured logic of the Air Canada buffoon, you won’t get any new benefit when Mapleflot begins charging low-fare flyers for a seat assignment.

Unless you’re a Zen master–and, I admit, frequent flying has driven us all to Zen-like forbearance–you cannot reasonably equate taking away from others to mean that you are receiving more.

At the beginning of deregulation, when the airlines could credibly argue that $198 customers were receiving $998 worth of service, all travelers received: full refundability of tickets; advance-boarding passes; no advance purchase rules or Saturday stays; no ticket-rewrite charges; the ability to choose the best seats available; and the freedom to buy tickets from any retail channel.

Over the years, the big airlines have forced leisure travelers (and many price-conscious frequent flyers) to accept nonrefundable tickets; advance-purchase and Saturday-stay restrictions; rewrite fees that have steadily climbed from $25 to $35 to $50 to $60 to $75, $100 and now $200; and now, it seems, pay-for-the-privilege seat-selection practices.

For the privilege of flying for $198, leisure travelers now have given up almost everything save their seat and their seat belt. How can the big airlines credibly claim that this somehow makes our lives as frequent flyers better? They can’t–and you shouldn’t let them.

The fact that leisure travelers now get $98 worth of service for their $198 ticket doesn’t change the fact that we’re still getting $198 worth of service for our $998 fare.