It's kind of funny with me, I think I enjoy the collecting aspect of gaming almost as much as the gaming itself. There have been some games I personally didn't enjoy actually playing all that much, but I still kept collecting because I liked the aesthetic/theme of the setting (The old White Wolf RPGs come to mind). When you can take a step back and look at an army that you've developed over several years, or a long-running RPG series that you've bought every supplement of along the way, it can be just as rewarding as being an active fan.
So when I go through a slump, I step back for a week or two, get worried about falling behind, and that usually snaps me out of it.