A large number of Nicor Gas customers are overpaying for a repair service that is rarely used, according to consumer advocates who argue that utility is improperly selling the service through an unregulated affiliate to divert revenue to the utility.

About 20 percent of Nicor customers are signed up for the service — Gas Line ComfortGuard — which covers the cost to inspect and repair a gas leak in a home. They pay $4.95 per month, but just 2 percent of those customers ever need the service, and the average payout is just 10 cents per month per customer, according to an analysis by consumer watchdog group Citizens Utility Board. Get the full story »