I like to keep "one day at the range" worth of ammo on hand, which means about 200 rounds for each pistol caliber, 300 rounds for 5.56, and 50 rounds for all other "bolt action" rifle calibers. I don't feel the need to keep 1000 or more rounds in reserve.
Last weekend I went shooting... I chose to shoot 38, 357, and 45 ACP practice ammo because I can replace those. When I shoot rifles next week (weather permitting) I will shoot my 243 because I can replace those cartridges.
I have 250 rounds of 9mm FMJ on hand, and I am reluctant to shoot any of that until I know I can replace it.
I have 350 rounds of 5.56 FMJ on hand, and I typically shoot 200 - 300 rounds of 5.56 per trip to the range. I am not going to shoot 5.56 until I know I can replace it.
If I had 1000 rounds of 9mm or 5.56, yes by all means I would be shooting it.