Whilst I agree with you to an extent you're missing the real point - why weren't there XL sized pyjamas available for your highest yield customers?
I can't answer that, but in the REAL world, sometimes stock runs out, or no one mentioned they were out of XL PJ's. Have you ever gone into a store and wanted something in particular and it wasn't available? If so, did you have a hissy fit in the store, stomp your feet and make a complete jerk of yourself, or did you ask if there was something of similar quality, style, look, feel, etc? Things get missed. Name me an organisation that is 100% fail-safe and never errs.
Do you like soy coffee? How do you feel if it's not available? Take anything you particularly like and value enough to pay for, now imagine if you don't quite get the full experience. How do you feel?
Not interested in soy coffee. Don't care if it's not available. Maybe it's me, but if what I want isn't available, take the next best thing or go elsewhere. I don't know how a set of PJ's give you the "full experience", but it's pretentious idiots like those two that have an overinflated opinion of their own importance, and think the whole airline has to come to a standstill because of their unimportant and illegitimate demands.
Whilst the customers appear to have been over the top in their reaction the real point is that somewhere the Qantas system simply didn't work to keep your most valuable customers happy.
Sure things happen and go wrong. That's life. Some people need a reality check if they believe otherwise. If one doesn't like a particular airline, there's plenty to choose from. But if your only gripe is a set of cheap cotton PJ's that have a brand name on them and made in China, not available in your size, then you have serious issues, regardless of how much you paid for a ticket. QANTAS has a BIG complaints department. Use that instead of making complete Richard Craniums of yourselves in front of a plane load of people.
If you ordered a Ferrari and got a Hyundai, and told that was all that's available, THEN you have a gripe.