With the pilot light continuously on flame is instantly available at the owner's convenience. This makes starting the fireplace quick and easy with minimum fuss. During changing seasons the need for additional heat is not always predictable; leaving the pilot light on makes for quicker access to comfort.
Cost and Potential Hazards
While leaving the pilot light on may be convenient, the continuous flow of gas may pose a safety hazard. Homes with smaller children may want to consider the potential for injury before opting to keep the pilot light burning. Added to the potential hazard is the constant consumption of fuel to maintain the pilot light.
The cost to maintain the constant flow of natural gas to keep it lit is minimal, possibly measured in cents per year, while the convenience may be priceless on a suddenly cold evening. Any safety issues can be avoided with proper equipment.