ISO 9002/AS9100 fixes everything and the goods produced are either perfect or scrapped at the point of origin. This is true if the product is a 35 million dollar airframe, if it's a 25 cent round of 9mm ammunition then probably no.
Comparing airframe to ammunition doesn't make sense. To suggest that ammunition is knowingly made with lower quality standards ignores the fact that ammunition poses a much greater risk to the person shooting the ammo than to a passenger riding in a airplane. (Just for the record there are a lot of rejected parts when making a airplane.)
This is simply a lesson in mass production and economy of scale. The principle is that more of a product I can manufacture without making any changes the lower the cost per unit and I will have a higher volume of production. By using my manufacturing capacity more efficiently I will enhance profitability.
You can prove this yourself if you own a progressive press. See how many rounds you can make in a hour by cranking out rounds with the same primer, power charge and bullet.
Next crank out the same rounds again for 30 minutes. Then stop and change the powder charge and resume production for the remaining hour. Your number of rounds you crank out will be lower.
However for manufacturer they are faced with how much ammunition they can sell which means either reducing production (reducing efficiency and raising the cost per unit) or reaching a different market. The tricky part is how do you sell the same product at a lower cost without diminishing the market for selling it at a higher price.
A simple effective solution is advertising and packaging of the product. Continue with expensive, high profile advertising such as glossy pictures using pretty models in gun magazines, etc. to appeal to the consumer who is willing to pay the higher price.
However it makes little business sense to ignore the market for people that cannot afford to buy it (leaving the market open to someone else). So change the packaging and reduce the advertising. The volume of sales will be smaller but the profit per unit will remain or maybe even be higher due to the cheaper marketing.
HOWEVER, and it is a big however, it is important that the manufacturer does not reduce the quality and reliability of the ammunition to avoid cheaping the name of the brand.
Want a real life example of this happening? Here is a little history lesson for you youngsters. (Gosh I wish I could be called that).
In the early 1980's Federal introduced their American Eagle line of ammunition. It was packaged in a white box with black print labeling. It was not heavily advertised.
One day we had a Federal factory sales representative stop in the gunshop so we asked him about the quality of the American Eagle ammunition. He explained that was the exact same ammo as was in box of the higher priced stuff. It was excess production and was sold at lower cost due to less fancy packaging and advertising.
Comparing Hornady American Gunner 124 gr. XTP +P to their Custom 124 gr. XTP I can not see a difference. They look the same with the only difference being the headstamp. The case and o.a.l. measure the same. The bullet looks the same. There are no manufacturing defects or evidence of lower quality such as dented case. The only difference I can imagine is with the different or reduced powder charge.
Most importantly it goes bang everytime I pull the trigger and gives good accuracy.