Yeah, one way is about $300 more expensive than a return flight.
I booked the flight 48 hrs ago... so couldn't get a free refund. A/C was stupid, and wanted me to pay $150 per direction to change my flight around. I told them I could just cancel for $200 and rebook, and she said I couldn't at first, but I insisted a T+ flight could... i told her to check with her someone, and lo and behold I could cancel for $200 + tax.
anyway long story short, by flipping my flight around, it would've costed me $200 (cancel fee), plus an extra $600 for a SYD-YYC-SYD flight. I ended up just booking business class on Jetstar to HNL, then US airways from HNL - YYC. ended up saving $600 at the end of the day.
what I don't understand is why A/C would cancel my return flight, even if I specifically tell them I will be using that flight. One lady says it's automated, but another lady told me someone physically will check, and remove me from the system. LOTS of conflicting information, and I'm not impressed at all. Oh well, lost my business for this flight home.