AFAIK NZ has no more 24 hour supermakets. I remember brisbane used to, but a quick google search shows that might not be true anymore?

When I was staying in South Bank, restaurants were regularly open until 9:30/10pm. Finding places like that in christchurch is much harder, outside of thursday/friday/saturday. Auckland might be better, but it's been a while since I've stayed there.

TBH, maybe it's not that brisbane is good for late night stuff, maybe it's just that NZ is even worse.