With all due respect (even though I live in Auckland and don't particularly like the place), Auckland has a 1/3 of the countries population, and no doubt the biggest sector of the dance music market in NZ living there, which makes it a no-brainer if you're a big act doing a one show only visit to New Zealand.
Promoters in Wellies just can't sell a headliner date compared to Auckland.
If you like the band so much and don't wanna miss out, I suggest you travel. Just as the numerous people in the States who have to travel even further than the pathetic distance between Auckland and Wellington, or even Christchurch.
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This one is gonna be around the corner of my g/f's place. The 2002 show was around the corner of my old place. Wicked...