This article mentions fares increasing due to reduced capacity to account for social distancing. Also there's an example of the fare increase. Yes, not the most reputable news source.
I wonder what the response would be if retailers started using this tactic for 'click and collect' purchases. Charging people more when they come to collect their items and then not offering refunds.
Hardly the best story either...
I looked at the Air NZ website after I read that that earlier and it was possible to get from AKL-DUN for $287 each way down Sat back Sun which is well within the normal range he pays.
As there are still only limited flight options even under L2 to get from from AKL to DUN next weekend you have to fly via CHC rather than direct, and there are only very limited flight options so only 1 possible flight option each way.
I'm not sure your analogy could be compared to an airline? Most retailers don't have 20+ different price points options for the very same product which is effectively what an airline has factoring in different fare class and fare basis options.