Probably pay to follow whatever octane rating the manufacturer recommends for your engine, so will make sharing a bit harder but yes the futures and location thing is interesting as you can buy up to 1000 litres at a time. I see Z are very careful not to market this as a way around the Auckland regional fuel tax but with the ability for motorists to buy up to 1,000 liters pre-paid from one region and use it anywhere...I think one of its advantages is plain for all Auckland motorists to see.
https://sharetank.co.nz/#buy-your-way
Probably a cunning plan and will gain them back a small amount of much needed market share.
How many Auckland motorists are suddenly going to find an excuse to visit Hamilton and husband and wife, (by some remarkable coincidence lol), decide to buy 1,000 litres of fuel prepaid each, while they are there ?