I have actually done very well in this area....because my approach is to have one good/quality item and not have multiples. I ask myself "Why own something if I'm not going to use it?" and "Why have more than one if I can only use one at a time?" My simpleton approach resulted in my being a one-rifle owner for nearly 20 years, and am on my third bow in 30 years. (Have since bought a couple of rifles!)
That being said, it took me a long time to find a pair of hiking boots for elk hunting that fit my feet really well. After a couple of seasons of trial and error, I found the right boots for my feet. Afraid they would change the model, stop production, or go out of business, I stock up on them whenever they go on sale....I have something like 10 pairs, of which 4 or 5 are brand new. They will get used at some point!
Other than that, I've got pile of diaphragm elk calls - never know when one is going to have the latex stretch out or leave it someplace!
And inexpensive headlamps....I use those things all the time.....have a bunch inside the house, in each vehicle, out in the shop......