Originally Posted by
YOWgary
Sunk-cost fallacy.
AC is betting that 25Ks will think "well, I've got all these upgrade certificates, and it'd be a shame to just let them expire..."
Honestly, I think this is all simply a revenue-management move, trying to find a way to further monetize expired eUps and squeeze out another $500/yr per lower-tier FF member.
At this point, AC are offering several different ways to pay to upgrade, all of which seem calculated to make the passenger feel like "oh, it's just a little more", when, as many have shown here, LMU, or co-pay, or whatever, comes out to almost as much, or even more than, simply buying the higher fare in the first place.
I think you are right on the psychology of this.. I am already thinking "it's just a little more, AC is allowing me to do it from Tango now, so why not. It is somewhat of a win-win for both parties. They make a little extra and I get to upgrade a previously unupgradeable itinerary (is that a word?)