Next up from the airlines – pay credit card fees to avoid other fees.

At first, the question was, would passengers accept airline fees? Now it’s, how many more fees can airlines pack on and how high can they go?

The latest angle may be, “What fees will travelers pay, to avoid paying other fees?”

United Airlines for some time has been one of the leaders in this department, selling all sorts of Elite perks from seating to baggage waivers.

And they have also offered expensive branded Mileage Plus Visa cards ($375-$475 per year) that offer Economy Plus seating or Red Carpet Club membership.

Now it looks like this branded credit card idea offering fee waivers may be trickling down to the masses. Continental has a deal with Chase to waive checked baggage charges for its regular Mastercard holders.

And now Delta and American Express are getting into the act. Starting June 1, holders of a $95 a year Delta SkyMiles American Express card will be able to check their first bag free for a year, along with their travel companion’s bag.

Business travelers may not be that impressed, frequent fliers often have elite status already and many try to bring only carry-on luggage anyway.

At the current $25 a bag cost, which of course is always subject to change (usually in an upward direction), that means the card would pay for itself in two roundtrips. Although, for a family, the savings could make the card worth it with, say, just one trip to Disney World.

But potentially the more interesting thing about these new deals is what new deals may come next. The possibilities are nearly endless, almost anything that has an extra fee, can have that fee waived for a credit card holder.

A few that come to mind, besides luggage, are seat assignments, the fee to talk to a human to book a ticket, onboard snacks and meals, etc. (Alcoholic beverages would probably be against some law.)

And airline branded credit cards are already tied to mileage numbers, so it would be easy to track the perks.

Most of these credit card fees start at about $65 a year and up, plus airlines get a cut when the cards are used. This could be another very profitable revenue source for the airlines.

So, Consumer Traveler readers, are there airlines perks that would entice you to spend, say $100 a year on a credit card? Whatever they are, you could, someday soon, have that opportunity.