Volume. Volume as compared to demand is always the key to pricing. Something that there is only one of in the entire world becomes incredibly valuable. Something as common as grass becomes worth very little. Then too, the market will bear whatever the customer is willing (and able) to pay. How much are you willing and able to pay for soda pop?

In my case, nothing. I don't drink soda pop anymore. They'd be out of business if most people made that choice.