The extra weight/fuel costs just shifts the price point where it's a good deal (as it makes the product slighly worse), it doesn't change anything fundamental to the argument.
Or to put it in another perspective: carmakers have never optimized for weight at the cost of everything else (as otherwise we'd all be driving around in cars made from titanium or carbon fiber). What's the difference between putting in a heavier seat with a non-functional heater to reduce production costs, and using steel instead of aluminium to reduce production costs?
Or to put it in another perspective: carmakers have never optimized for weight at the cost of everything else (as otherwise we'd all be driving around in cars made from titanium or carbon fiber). What's the difference between putting in a heavier seat with a non-functional heater to reduce production costs, and using steel instead of aluminium to reduce production costs?