It's a PSA on all the gas pumps. Drive off from the pump without paying for your fuel, get caught, and it's an automatic license suspension. Not sure if it applies to stealing fuel in other ways though.
I know it is on the pumps. The way he worded it, makes it seem that if you steal lawn mower gas from a garage, you lose your license.
This is best choice, fix Security lighting and be sure that your fuel pumps are fined lit and easily observable from the road.