Never ever buy games at full price, but I'll happily sink money into computer upgrades.
If I really want a new PC game I'll get it through CDkeys or if it's bundled with a PC part I'll usually buy it from someone who doesn't want it. If I really want a new console game I have friends/former coworkers who work in an electronics store who give me their employee discounts. Otherwise I'll wait for sales. Unfortunately used game prices here are a fucking joke, so I don't buy used games that often.
I did, however, get a PS4 pro as soon as it came out (don't have a 4K TV, don't care, I'm still very happy with it!), built a beast of a gaming PC last year and just upgraded the CPU two days ago. Did I need to? Nope. But I had the money and felt like it ^^
Some months I spend 100€ on games, most months 0. Just depends on whether I've got spare cash and there are games out that I want.
E: I realize this post may seem a little flippant, but I do realize that I'm super privileged to have a well-paying job and disposable income.