I contacted Costco's customer services line today and asked one of their front line reps, Judy, a few questions as to where Costco sourced their gasoline/petrol supplies (as in primary country of origin).
Costco's explanation was, in general, as follows
Costco does not discriminate and will rebuy processed gasoline product from wherever it makes the most sense to maintain the buying power of Costco members.
So, in short, they buy from a variety of refiners, probably similar to most independents out there.
Judy's statement from Costco that she was reading from actually sourced snopes.com for information about FAQs about recent (and not so recent) questions about boycott attempts against certain suppliers and directions to purchase from particualar ones, to make a political or economic statement. Quite interesting that!
I also asked if they bought crude supplies or were in any way vertically integrated. They do not and are not. I asked, too, if they bought gasoline contracts, similar to the airlines for their JP4 and other fuels. Also "no".
Asked if they always had the lowest price. Again, due to fluctuations with pricing, they may not always be the least expensive at any one particular point in time.
More interestingly, when I asked if it would ever be advantageous for Costco to announce a country or contries of origin where gasoline/petrol is sourced from, from a marketing or promotional perspective, the customer service rep volunteered that this could be a possibility and not outside the realm of consideration.
Judy's candor and honesty were quite refreshing (as much as any corporation is allowed to reveal of its business practices/"special sauce").
