Without reading up about this history, I have no idea about the context and the particular details there. Was that energy market they were participating in an actual free market, or heavily regulated to prevent easy competition? I'd guess the latter, but can't definitively say so.

But in general, if there's free entry into a marketplace, there's a check against this sort of behavior. Rising prices are not bad: they are a flashing signal that society desperately wants more of a particular good and to provide more of it as quickly as possible. If company X tried to cut production of any good in an area and boost up their prices, every entrepreneur out there gets a neon flashing message that there's a new way to profit mightily if they can provide that good.