I don't bother doing OLCI if I'm seated in an exit row. When I fly to the US I put my Canadian passport info in the booking (no ESTA required), maybe the system flags me because of that. No clue. I'm flying to the US next week and again in early January so I'll make sure the state is entered correctly.
It only came in recently but if you're a dual national ie Australian plus something else (when travelling to the USA or New Zealand at this stage) the airline will need to contact the Australian Immigration EOC (Entry Operations Centre) when you checkin to obtain an authority number which link both your passports which is something to do with Smartgate trials.
This is because when you depart Australia you would be giving your Canadian Passport to the CSA at checkin to show you're exempt from a visa or ESTA for the USA. If you gave your Aussie passport to the CSA & no ESTA is found then you would need a secondary document such as a hard visa eg if you were studying in the US or a green card proving your eligibility to reside in the USA.
When leaving the USA you would of course do the reverse and hand over your Aussie passport when you checkin in the USA or Canada otherwise if you used your Canadian one you would need to have a visa for Australia which of course you can't have if you're an Australian citizen as you must depart and arrive Australia on your Aussie passport.