Originally Posted by dmp1991

If the point you're trying to make (not sure I've interpreted your sentence correctly) is that a free upgrade due to premium status is not really "free" to me, then I completely disagree. I did not spend any "thing" to get that upgrade. Yes, I had to earn the status somehow, but I didn't do that in return for that particular upgrade. Said another way, I don't acquire status solely to get a chance at a free upgrade every now and then and I doubt the majority of status passengers do that -- certainly not on BA where upgrades are very, very rare IME. IMO, it's likely the bulk of status card holders either acquire status as a by-product of a need to travel, or acquire it for a large portion of the whole of benefits offered by having status (picking seats, lounge access, additional luggage, less likely to be denied boarding, GUFs, etc.)

Whereas, if I spend "points" out of "my balance" at my own discretion to acquire an upgrade, and for which the "points" could be spent on other items directly equivalent to cash, then I am paying something to the airline in compensation for the upgrade. They even get to set the price! So I'm effectively paying with cash at the rate they set. If the timing of the payment matters that much to them, make the upgrade cost high enough that people either won't or can't pay "points" often, but frequently get a better deal by buying the target class at original purchase.

IMO, it's just silly for the airline not to offer you the opportunity to buy any empty seat whether paying cash or "points" or Avios.

As a parallel, how should we classify letting passengers buy food on board the plane for Avios? Is that equivalent to giving away food for free?