I've gone through several stages of collecting. When I was younger and jobless I would sell games as soon as I thought I was done with them so I could buy new ones. When I first got a paying job I started "collecting" in the sense that I didn't sell off games I liked so my collection grew. I still sold off mediocre games, etc. Around 25 when I got married and moved into an apartment with my wife I sold a lot of stuff off. Stuff I actually enjoyed but I just didn't have the space and I thought I was "moving on" with my life, etc. (Bullshit in retrospect) Sold most of my big-box PC games, the Genesis, N64, etc. I was only keeping the current, modern stuff (except for NES which I've never stopped collecting). Fast forward about 10 years and I've gotten back in. I'm not really a huge "collector" per se, but I do enjoy retro gaming quite a bit and like to have all the old systems and play them on a CRT. I have a small collection of good games for each of them, but I in no way want to have a complete set or anything even close to it. My entire physical collection (boxed PC games included) is less than 1000.
Video games are more than just nostalgia or disposable entertainment for me, it's a true hobby, something I research and learn about. I enjoy knowing the history, reading the books, and playing the more obscure games and systems. I have no interest in sports, cars, or other things most people enjoy, so this is what I do and I'm quite happy with it. My wife is super into quilting and spends a good deal of time and money doing that just like I do with games and we get along great. I'm pretty lucky all things considered.