It may be... the cheap price is shipped and sold by a 3rd party vendor, the ~$10/qt price is shipped and sold by amazon. The 3rd party vendor probably only puts so many up at a time and when they're gone it reverts back to offereing the ones shipped/sold by amazon. I'm guessing my order of 24 emptied them out.
That being said, I do take a higher risk that I get counterfeit goods, but even the cheapest, bottom barrel fluid is $2/qt, I can't see them scrubbing labels and putting new labels on for a profit of less than $2/qt so I'm inclined to believe that guy just has a way to get it cheap. We'll see when it gets here.