My game collection really ramped up at a time when I had a regular group of players, but most of them weren't buying games yet, just playing mine. Once they started buying games and bringing them, I needed to cut back on buying games, but it took a while until that sunk in.
Life is too short. I don't give a fuck about my collection size if I can store it no matter how many people (for good reasons!) talk about only keeping games they play regularly, consumerism, etc.