Why do a lot of businesses lean towards hiring 2-3 part-time people to fill the positions of 1 full-time person?
Its cheaper to run 1 refinery at 120% production than to run 3 at 90%
You get to save money on the costs of the other refineries (by not operating/closing them) AND... you get to reap the benefits of the price increases due to the pseudo-shortages in production!
Problem with your incorrect theory is that the refineries in question are (or, in many cases, were) operated by multiple competing entities. Yr just spitballing here.