Yeah, I follow that rule too. Another potentially dangerous act is filling portable gas cans. An approved gasoline container also dissipates static electricity (yes, even the plastic ones), as long as it is placed on the pavement before filling begins and the nozzle touches the container during fill. Leave the can in the trunk or pickup box, however, and it is a different story. A trunk liner, bed mat or bed liner insulates the vehicle/container from the ground and the static buildup of electricity has nowhere to go. Static buildup occurs and if it releases, the resulting spark can set off the gasoline vapors coming out of the container. Does not happen often, but it only takes once to ruin your day....