Everyone knows, weight is bad in airplane design.
But, when they were designing the Boeing 777-200ER, a plane that weighs something like half a million pounds, they calculated for flying a 3,000-mile flight, cutting 2,500 pounds could save about 23,250 gallons of jet fuel.
At an average price of $1.66 per gallon, that's almost $39,000 saved on one transcontinental flight.