I might note that "volley fire" is about the opposite of saving ammunition; it is inherently wasteful and rarely produced any positive result, even on enemy morale. But it sounded good when someone said it fast.
Sure, in some tactical situations, supply of ammuntiion (and everything else) can become critical, but I say again that ammunition usage, in general, was not a big consideration in rifle design; the German and Japanese rifles never had cutoffs, the designers feeling that clip loading allowed reloading fast enough. The British took the one off their SMLE; their Pattern 1913/14 and the U.S. M1917 never had one, nor did the U.S. M1 rifle. That was due to changes in tactics; had "wastage" of ammunition been a serious concern, semi-auto rifles would never have been issued.
Even so, small area shortages did exist, fire discipline needed to be exercised to save ammo; that was a command problem, not one of rifle design. Still, the adoption of the M14 was said by the Army to alleviate the condition in which soldiers armed with the M1 would fire off the remaining rounds in a clip and reload with a full clip when expecting action. So ammo wastage was not unknown or ignored.
Just to put things in perspective on ammo supply. In the period from late 1941 to mid-1945, one U.S. factory, the Army's Frankford Arsenal, produced 1.2 million rounds of .30 ammunition a day. There was no overall ammuntion shortage, even for the Germans. I knew a U.S. Army captain who was assigned, after V-E day, to inventory a German arms and ammunition depot. Among the stores was 5 million rounds of brass case 7.9mm ammo that had been turned back by the Luftwaffe as not up to their standards; it was being held for issue to ground troops, but the destroyed rail and road networks prevented it being shipped.