I am also a bit down on expansions myself. Sometimes they do add a lot to a game either cleaning up rules ambiguity or enhancing re-playability. More often than not, however, they add unnecessary clutter to a game (my #1 example of this is Cities & Knights for Settlers of Catan -
imo an expansion that destroys the game for me) or, worse, add nothing in terms of clarification, enjoyment or re-playability (Munchkin and its seemingly dozens of add-ons in guilty of this but I really hate the game itself so I might be biased here).
Fortunately I seemed to have killed my collector personality dead long ago with Magic. That was one game I was completely obsessed over for a long time. I finally sold my collection 5 years ago and haven't gotten into the mentality of needing everything for a game since.