This is not pumping any additional oil. This is taking the oil they normally sell and refining it. Then the refined product is sold at a higher value.
All the more evidence for Peak Oil.
Crude oil production is probably 10-100 times more profitable than refining. If you have plenty of crude oil, it makes no sense to refine it (beyond whatever amount your nation uses), since the resources invested for refining would be much better spent in getting the oil out of the ground.
On the other hand, if your crude production is peaking, then it makes sense to diversify into less profitable ventures such as refining.