Infrastructure needs new investment, energy companies have cash and engineering skills. I am most familiar with the water industry. Every part of the water infrastructure is aging. Water pipes have a useful life of 50 to 100 years yet most utilities have programs that will replace pipes on average after 200-500 years. Other have no plans.
Energy companies have the cash, skills, and size to rebuild the aging water infrastructure.
Finally, they know how to operate in the regulated environment. Consolidation, on the other hand, carries both financial and political threats. In a merger frenzy, some energy companies are paying four times book value for a water company. It is difficult to see where economies of scope and scale can permit recovery of these investments. In the regulated sectors, this problems will fall on the floors of state Commissions.