These are sale fares so changes are always going to be problematic, when your paying $400 for a fare vs $600 you have to factor in the value of changing, in many cases with QF doing it online is not easy or possible anyway, it's hard to see the downside given the outlay, and given we are talking about fuel surcharges not really worth talking about in J or F context.
I think you're misunderstanding the point. This is not about the cost of changing, it's about the
actual process of changing and some of the difficulties associated with that. This applies to both voluntary and involuntary changes (i.e. schedule changes).
The plain fact is, talking to QF agents is far easier than talking to Expedia Brazil. Yes, you can
effect a change by calling Qantas (and there is the "upgrade trick"), but sometimes they will still flick you back to Expedia Brazil because .br issued the e-ticket (and they still need to).
I'll give you my experience today - pretty much dodged a bullet.
Dad is travelling BNE-SYD-MNL tomorrow (has been discussed in thread before). Originally a different date for outbound and MNL-BNE non-stop for the inbound. The inbound changed to via SYD so one involuntary change, then SYD-MNL on the outbound was cancelled on the original departure date so another involuntary change (the latter not so preferable). Long and short, I called QF (as some said to do here) and a helpful agent modified the booking and sent through a change order so that Expedia Brazil would pick this up so they could re-issue the e-ticket (Qantas, not being the agent on this booking, could not - or rather, would not want to, for the purposes of not messing with commissions - do this).
Called Expedia Brazil a few times and each time it was pretty hard to get them to, in essence, re-issue the e-ticket. The last time I contacted them I thought it was all honky-dory. They confirmed the final flights on the booking and started processing the e-ticket. They mentioned something like having trouble re-pricing the ticket with Qantas, but having not been contacted by them again I thought it was OK. Checked my booking with CMT, MMB and a few others; seemed fine.
Come today and T-24, we tried OLCI - no OLCI on QF MMB; in fact, the Select Seats button was still there. That's not right.
Called Qantas Gold to discuss my Dad's booking, and they found out that the e-ticket had not been re-issued after all! Turns out there was a bit of tete-a-tete between Expedia Brazil and Qantas over the re-issue (not a lot of detail shared by the CSA, but from the impressions of the discussion that's the gist I got). The helpful agent and her supervisor decided there and then to issue a new e-ticket under the same PNR so my Dad could continue flying tomorrow.
Needless to say, that was a close call; I wouldn't see the light of day tomorrow if my Dad flipped finding out that he wasn't travelling as planned.
Anyway, yes - you could argue that that's the fault of agents, or myself, or what not. But I'm just saying, there is that inherent increased difficulty in potentially having to deal with Expedia Brazil related to changes or irregularities in bookings before the commencement of travel. Basically a similar tack to booking with any other travel agent.
Yes, if
absolutely nothing goes wrong and no changes are made to tickets, then everything is pretty much the same, except with Expedia Brazil you have a much cheaper Y ticket. In at least 80% of times, this is certainly the case. Personally, I can roll with those punches for the remaining 20% of the time in order to save a few hundred dollars. Some won't want to, especially if they are not seasoned travellers themselves, or don't have the support of someone who is so seasoned.
. Having booked 8 last year, threw away one, I did not miss much at all, MNL changes are somewhat OT given the thread is titled about SIN 
