US has fielded steel-cased ammo in the past (1943 .45acp).
Yes, yes we did. Do note it was the same year we fielded the zinc/steel penny, and ONLY in .45acp. Even at the height of wartime shortages, we did NOT use steel cased rifle ammo (and as far as I know the steel .45acp stuff came only from one location EC 43), and we went back to brass the following year (44), when demand for ammo due to combat was actually greater.
I don't like steel cased ammo, and I don't buy steel cased ammo, other than some 7.62x54R surplus copper washed stuff that was so unreliable, I gave it away.
Steel cased ammo wasn't created simply as a lower cost alternative, it was created as a military expedient, that happened to cost less and worked well enough for military use, in the eyes of those nations that adopted it.
Personally, I happily pay more for brass cases that I can reload (boxer primed) or Berdan primed brass that has a higher scrap value than steel.
It MAY not be crap, but I don't see steel cased ammo in other than a few military calibers, and with my shooting habits, steel's cost advantage simply doesn't outweigh the disadvantages.