They're mass produced on assmebly on a factory assembly like an expensive Omega!
Still, I like where this is going, is a chunk of steel really that much more expensive than a chunk of plastic anyway? RM gets away with it on their zillion dollar Nadal tourbillion, and I think the new GP Circuito is of similar material.
If this picks up and I can pick up something like that for 1/4 of the price from Hamilton that'd be an automatic sportwatch I could wear 24/7 without any discomfort.
Breitling lists the Avenger Hurricane at 69 grams without strap vs 150 grams for the Super Avenger without strap, so the difference is monumental.