dissenting: I respectfully dissent from the well-written opinion of my learned colleagues. I note first that the existing rate structure is presumed to be just and reasonable and that the burden was upon the appellants to show that it was unlawful. Moreover, the findings of the Commission are conclusive if they are supported by competent material and substantial evidence in view of the entire record, and I conclude that they are so supported in this case. Incentive rate structures based on use intensity are widely authorized, and the question of their employment should generally be a matter for the specialized regulatory agency and not the courts. If appellants pay more for the petroleum they buy than others, that result springs from the pricing policies of the oil companies — a matter beyond the jurisdiction of the Utilities Commission. I vote to affirm the order.