I think it is simply a health and cleanliness thing that keeps them from refilling.
I did not try the Aotearoa. There were too many new beers, I had to drive, and it's been a long Kasteel Rouge drought, so I had to give it a pass. If it's there next week I'll give it a go. Right now, it's 11:15 PM and I'm enjoying some Hell's Black before bed. A wonderful brew.