I buy as needed of if I can find a good deal on something. I still have a set of original TreeBark from the early 1980s (retired) that I colored with sharpie markers when it faded to extend their life. No telling how many camo gloves and headnets I've lost...dozens for sure. I've lost a few of those gun rests that go around your knee. I always have a backups ready, no matter what it is. If a buddy forgets or loses something, I've always got a spare.
Jim