On this particular night, it was possible to buy the same drink at prices ranging from $1 per litre, all the way up to $7.40 per litre. Not only was it the same drink, but it was being sold in the same super market, in the same aisle, and all the packages were on shelves right next to each other! It should not be possible, but some people are being charged 740% more than others (per drink) for the same drink, just because they chose the wrong bottle size!

The first thing I wanted to do was put together an arbitrage strategy using supermarket coca-cola. A 740% risk free return is something I'd happily do all day. Obviously you can't repackage and resell the coke (at least not legally), so alas my dreams of instant wealth are still on hold.

I understand that there is a convenience factor so we pay more when we buy in smaller bottles, but this does not explain the pricing of cans. Why would anyone pay $12 for a pack of 10 cans, when they can buy 2 6 packs and get 12 cans for $10. The fact that the supermarket is able to sell in this way shows that I am not the only one who is price indifferent when buying coke.

The supermarket has shown me that we are either indifferent to price, or are willing to pay a hefty premium for the coke to be in a glass bottle. To s00ee if we are truly price indifferent, I decided to look at how much different shops charge for the identical coke product. I decided to look at the 600 ml bottle (served out of fridge so it's ready to drink). This is what I usually buy on impulse for an instant fix of sugar and caffeine.

This part of the study was conducted in a part of Sydney known as Bondi Junction. It is a very small area consisting of a large number of shops. It took about an hour to walk through the junction and visit a few shops to look at the prices, my findings are shown below: