I've never been one for buying plastic tat and have largely curbed my physical media buying habits - I haven't bought a physical movie/book/comic in years, and now own so many board games I am getting rid of some rather than buying more. My main vices these days are food & drink (I keep a small cocktail bar) and things like camping/hiking equipment and camera gear. I own far too many cameras and will spend an inordinate amount of money 'upgrading' various bits of camping gear in order to shave a few grams off my trail pack weight, which I will keep doing knowing full well how silly it is.
In terms of geek stuff, I will still occasionally get that 'gotta have it' feeling. Recent examples are the new Mega Drive Mini, that funky looking Playdate boutique handheld console and that Folio Society edition of A Game of Thrones... However generally I'm fairly good at resisting the temptation, and usually find that after a few months have passed I didn't actually want that thing as much as I thought at the time.
I can also be a bit of a sucker for backing cool stuff I see on Kickstarter, but generally if I take a step back and think to myself 'would I buy this if it were available to buy right now?' the answer is usually 'no'.