re: US Dept of Energy preparing to start SPR refill purchases

It sells on the global market in order to get the best price. If you limit outside buyers really you would likely only screw yourself (i.e. the taxpayer). The stockholders of the buyers would still profit though.

Even then, you could have someone like P66 or potentially a mid-stream play to blend the crude then sell it on the open market as a refined product.

Honestly, the sale shouldn't be happening and the buying shouldn't be happening right now, but Congress moves slow (by design) and have zero chance of reacting to market changes because of the design.