"Whoops I made $600 from something that cost me $10"
I've written about this here some time ago - you don't pay for the soap dispenser or trash bin itself, you pay for the paperwork showing that it is safe to install this trash bin, soap dispenser or whatnot into this specific model of aircraft or spacecraft, and you pay for the paperwork that details the entire life of every tiny little piece used to manufacture that component. For flight-critical parts, IIRC that goes as far as to documenting the specific lot of the iron ore that was used to make the metal sheets, so in the event of something cropping up where something got fucked up in the mine or the smelter, you can recall every single part that could be affected. And there's lots of testing (and associated waste) at each part of the step.
Anything that goes into an airplane or spacecraft has ridiculous rules attached to it... rules that were literally written in blood. Aerospace is amongst the safest ways of transportation because of decades of crashes and learning from each and every single one.
Your average Home Depot soap dispenser has none of that, if it breaks it breaks.
Surely there's a more cost-effective happy medium somewhere between "just buy the Home Depot 2-for-1 special" and "we ran a background check on the guy who mined the metal"
If a piece of military hardware or software fails, one or two or a dozen people die... if they can't eject.
If a piece of civilian hardware or software fails, hundreds of people die. Witness the 737 Max.
The breakdown of the barrier between the military and commercial sides of Boeing has resulted in a catastrophic reduction in quality on the civilian side. So overcharging for soap dispensers on the military side is far more egregious than overcharging for them on the civilian side, because the stakes are actually lower.
I'd actually disagree there. The stakes for military aircraft are higher - assume Russia or China sends a nuclear bomb equipped squad on their merry way to Alaska.
If even one of the US planes has an issue taking it out of the fight, the Russian bomber squad may succeed, dropping a nuke and killing tens of thousands of people.