In some respects I can agree with what they are saying, but effects on the balance sheet are the true "reason."
Margins on gas and oil are relatively stable, but when the price of the products double's, you still need to buy the product before it is sold. You need to make up that price difference with either borrowing more money or contributing more equity to buy inventory. If you buy more gas reserves or have to pay more for those reserves, you must borrow more money and pay more interest. It also, gets banks (ie creditors) nervous when they see a huge increase in liabilities and a correponding increase in leverage.
The point about the uncollectible bills, may also be to blame, as when the cost of a gallon of oil doubles, so to will the likelyhood that losses will double. The rate of uncollectibles is relatively stable, but if the cost of the oil is double, you have just doubled your losses.
Conservation, self imposed or not, leads to lower volume and requires an increase in margins or a decrease in overhead to maintain profitability. They chose to increase margins.