There is a point of diminishing returns with buying new gear.
For example, I use a silnylon tarp. Standard 8×10. 13 oz. Call it just under a lb with stakes and rope.
I could buy a cuben fiber tarp. But is $300 worth it to shave a touch over 3 oz?
I do have a new pack, but my old one finally went kaput.
Stoves? I have a decent canister stove (Coleaman F1) for when alcohol stoves are banned and/or I don't want to go stoveless. There are lighter canister stoves now, but, again, do I really want to spend more $$$$ to shave 1.5 oz? Likewise, I could buy a remote canister stove for winter use..but do I really need another stove when white gas works well enough?
I find my gear purchases are when things wear out more than anything at this point in my hiking 'career'. I do occasionally buy new gear as my *needs* dictate vs my *wants*.
Not that I am immune to minor splurging. I did buy a $20 down beanie off e-bay to try out. ;)
To add to what Nick said..not only will getting out there and using your current gear make you less likely to do big gear purchases for the 'feel good effect', but by using your gear you eventually wear it out and *have* to buy new gear. Win!
I honestly think a lot of buying of gear is that gear itself can be the hobby. Nothing wrong with that per se. But when the hobby of gear collecting is no longer as satisfying, then you may find that you will stop changing gear so often.
Just my .05 worth.