How about having digital fuel gauge to neutralize the rampant fuel theft by pump operators?
The recent cars displays predictions on the odo, about the distance the car can go with current fuel quantity in the tank. Then why not have digital fuel gauge. Before refilling, note how much fuel is in your car's tank. If you add 10 lts of fuel, check whether it reflects in your odo.
This will prevent fuel theft by the pump operators.