That is, as I understand it, not what we are talking about in the case of Enron. Like it or not, Enron was a well respected player in the commodity energy business. They effectively made markets by matching buyers and sellers of energy. They understood the way that energy in all its forms could be arbitraged, in order to create efficient energy markets. Simply put, they were the experts in this industry. Even their competitors (and I used to be one) grudgingly admired them. They took a 100+ year old industry and shook it up, and nothing that has happened over the last year has changed that.
They were cocky and arrogant, and their hubris and their lack of integrity were their downfall. However, that in no way changes the fact that if you were drafting an energy policy in 2000 and 2001, you could not do a good job, or exhibit anywhere near the necessary due diligence, without talking to Enron, the biggest innovator and most successful company in the industry.
This is no different than any other policy formulation process. You have to gather information first, and you do it through interviews of the experts in the field. I did the same thing myself, working on Capitol Hill. Congress does it all the time, by having experts testify before the committees, as they draft legislation. Do you consider them lobbyists? Would you be happy if your government were creating policies without the input of those affected?